Maybe r/crafts might have more answers?
I use a scrapbook-like adhesive machine (Amazon Link: Xyron Create-a-Sticker, 5", Sticker Maker, Machine, Permanent Adhesive (0501-05-10A) ). You feed the paper through the rollers. Bottom rollers have sticker adhesive that transfer to the back of your paper. This machine uses a hand-crank on the side for the rolling mechanism. It also applies wax(or parchment?) paper that you peel off to expose the adhesive.
I suppose you could also apply glue on the back with a brush? Not sure what type of glue you would want to use though.
My wife bought me a make your own sticker contraption. You print something out, run it through, and it makes a sticker. Pretty slick little thing. $15 on Amazon.
I want this bad boy. Do I need it? Nah. Do I want it? Heck yeah! Think of all the sticker possibilities! I pen pal a lot and I think it would be really fun to send my own stickers to pals.
Well here's the thing, I'm getting a book that's going to be like custom made for the cover and basically i need to stick things into the pages. I was thinking of buying this to apply adhesive to my printed papers and sticking it into the book. http://www.amazon.com/Xyron-XRN500-Create---Sticker-Machine/dp/B000WWGANC/ref=sr_1_1?s=arts-crafts&ie=UTF8&qid=1439782783&sr=1-1&keywords=sticker+printer
There are sticker makers you can get at craft stores that can re-apply adhesive.
https://www.amazon.com/Xyron-XRN500EN-Create-Sticker-Machine/dp/B000WWGANC
Xyron Create-a-Sticker, 5", Sticker Maker, Machine, Permanent Adhesive (0501-05-10A) https://www.amazon.com/dp/B000WWGANC/ref=cm_sw_r_cp_api_glt_i_0AAFN82DQ96SZ95BFM8X
You can make stickers out of anything flat with this! Xyron Create-a-Sticker, 5", Sticker Maker, Machine, Permanent Adhesive (0501-05-10A) https://www.amazon.com/dp/B000WWGANC/ref=cm_sw_r_cp_api_glt_i_7H6EX3BWT96QWEDFBMRY
I design labels in Gimp, print them on any printer, cut them down and run them through a sticker machine