Freebie Sources - Not in any particular order.
1. In your inventory, at the very bottom, you will find "Library" - look in there, you will find lots of things, including a large pink flamingo....
2. In the Marketplace you can put in the name of what you are looking for and then put "0 to 0" in the price search box and look for freebies there.
3. "Official" Freebie Sites:
Mole Mart: http://maps.secondlife.com/secondlife/Leafminer/191/121/34 Building supplies - Road signs, pavement textures, other useful things made by the moles.
Nautilus Warehouse: http://maps.secondlife.com/secondlife/Nautilus%20-%20Shalim/231/112/25, textures, and other items appropriate for Nautilus.
Stillman Bazaar : http://maps.secondlife.com/secondlife/Stillman/148/89/23 - a small but well-curated selection of items and textures. Here you can also find Old Library Inventory.
Help Island Public: -http://maps.secondlife.com/secondlife/Help%20Island%20Public/158/115/21There are some things here you might not see elsewhere, and also a lot of information for new residents.
NCI at Kuula: http://maps.secondlife.com/secondlife/Help%20Island%20Public/158/115/21 - not only a well-organized assortment of freebies, but there is often a volunteer here who will be able to help you if you have any questions. Look over by the info counter for an info notecard that has good advice on finding free or inexpensive clothing.
Bay City Airport: -http://maps.secondlife.com/secondlife/Hau%20Koda/54/62/26 look on and behind the counter marked "Bay City".
Bay City Community Center: http://maps.secondlife.com/secondlife/Daley%20Bay/237/36/25- a large room full of assorted freebies.
Port of Kama City in Zindra (note this is an adult location): http://maps.secondlife.com/secondlife//120/21/25 Go up the stairs and left past the first two columns. The dispenser has mostly large structures.
The collected works of Arcadia Asylum and her alts (including Aley Arai, Lora Lemon, and Aley Resident) are also available on the Marketplace at AleyMart, but you can see them in person at the two spots below.)
Calleta: http://maps.secondlife.com/secondlife/Calleta/89/246/40 A nice collection of
Arcadia Asylum's Slum City objects in two old buildings and around the area. Be sure to go upstairs to see the reproductions of old video games. !
Mieville Pond - Arcadia Asylum Library: http://maps.secondlife.com/secondlife/Mieville%20Pond/138/63/21 around the water and under the water. There are buildings with vendors, but many of the items have been rezzed so you can see what they look like, rather than just seeing their picture on a dispenser. There's even a circus tent!
New Resident Services:http://maps.secondlife.com/secondlife/Lawst%20Paradise/102/33/22 Lots of helpful advice and free items - This area is supported by a private group.
Freebie Galaxy: http://maps.secondlife.com/secondlife//80/84/16- fourteen floors of freebies. Be advised that I have seen things for sale here that were free elsewhere, but it is certainly worth visiting at least once. Look out for griefers.
Sky High Freebies: http://maps.secondlife.com/secondlife/Gordon/93/152/2503 this one is new to me - just a big square of small shops, but what I liked about it is the fact that many of the small items are rezzed so that you can see what they look like.
Newbie World: http://maps.secondlife.com/secondlife/Trifolii/70/89/27 - boxes and boxes of things, and some rezzed examples. Also an amusement park, dance club, and "Newbie University".
NCI at Hanson: http://maps.secondlife.com/secondlife/Hanson/123/91/100 (quieter than Kuula, and in snow country)Hanson was an infohub area which was turned into parkland. Go over the bridge to find an old Gingerbread Cottage, a sled ride, and the amazing disappearing moles!
Simple's Zoo of All Things: http://maps.secondlife.com/secondlife/Plebeja/214/189/223 In the Mountain Retreat area you can find boxes and boxes each containing multiple items, but you should climb up to the top and explore the other areas http://maps.secondlife.com/secondlife/Triphosa/21/17/55 There's even a place where you can go hang-gliding!.
Virtual Railway Consortium Headquarters in Tuliptree: Everything you need to build your own railway system - lots of good information here, and a free locomotive!http://maps.secondlife.com/secondlife/Tuliptree/110/153/30
.Chilbo: One of many communities which have a focus on education: http://maps.secondlife.com/secondlife//118/221/118 - Start at Town Hall and do the tour - you will find freebies almost everywhere, mostly geared towards educators.
Freebies from Hunts: Hunts are a popular activity in Second Life. Merchants like them, because they get customers into their stores, and hunters like them because they get the fun of a hunt, and free or inexpensive items. You get a landmark for the start of the hunt and look for the hunt object - when you've found it, it gives you a prize and the landmark to the next store or location. Hunts vary tremendously, my favorite is the Silk Road Hunt, which in 2016 had 66 merchants participating and introduced me to many new places to spend money.... http://historicalhunts.blogspot.com.
SL Hunts: Actually this location mainly has a directory to their website:
https://huntsl.com, but it is good to know they have an in-world location as well. http://maps.secondlife.com/secondlife//55/108/398
Fashion freebies: I have to admit that I'm not a clothes shopper, but an NCI volunteer has put together an excellent notecard on how to get free and inexpensive fashion. Pick up her notecard by the information desk at NCI Kuula and some other locations, and look on the schedule for her classes.
Scripts: My current viewer has a "Script library" button under the "Content" tab which directs you to a website, but there are other online sources for free scripts - you just have to look. If you want to make your own scripts, the Second Life College of Scripting, Music, and Science has inworld free tutorials, although you can buy the lessons as a collection.http://maps.secondlife.com/secondlife/Horsa/177/244/2165
Some Notes: Just because something is free doesn't mean it is without value. Many generous residents like to share their talent. Other times new businesses may want new customers to try out their products.
A sad fact is that some merchants will re-sell freebies, especially on the Marketplace. It is good to know what is available for free before you pay for something that someone meant to be free (I've done that). Remember the pink flamingo in your Library? Gee, there is an identical one for sale on the Marketplace for 5 lindens.
Sometimes, though, what looks like a copy of a freebie may be an old item that has been re-made with sculpties or with mesh, so always check carefully before jumping to conclusions. If you feel you have found someone selling a 'free' item it is courtesy to notify the original creator so that, if they are interested, they can notify the Marketplace cops.
Sometimes older items are free because they have a high prim count. It is always a good idea to open freebie boxes in a sandbox. Even if an item has more prims than your budget can afford, you may be able to take it apart to see how it is made, or there may be some parts you can salvage.
Even if you never collect one freebie, I suggest you visit a few freebie sites to get an idea of what is available.
By the way, once you've started collecting freebies, you should know that both Builder's Brewery and Happy Hippo offer free classes on "Managing Your Inventory".