I never throw away packing tissue I receive with parcels as its always useful for collage & even stamping on. The above background was simply stamped with blueprints , then crumpled up prior to swiping with distress inks & spritzing with water.
This background started off as a piece of tan tissue paper to which I applied rusting solutions through a square mesh stencil .......quite a neat effect & textural in real life, the scan really doesn't do it justice!
Here are a couple of ATC's made with the first backgound above.
Other Free Cheap Tricks:
Use your old phone book yellow pages for glueing, once the page is sticky just turn over & use the next one.
Use phone book pages as part of your background (as in the ATC below)......picked up this trick from Claudine Hellmuth's book - Collage Discovery Workshop.
Collect & incorporate used postage stamps (as above) in your art & you can even cut out the images from some to add to your collage if your don't wish to include the whole stamp. The butterfly in the example below was cut out from used US postage.
Masking tape which is relatively cheap from any Hardware/DIY store can be used to also create textured backgrounds as in the deco cover above.
When you think about it there are a ton of things you can use in your art for free, you just have to look at things with a different eye!