i was at wal-mart a while ago and found the sand paper i needed in the paint section. in the same area i found some puddy spreaders and a scraper. the puddy spreaders were less then a buck for three and the scraper was like 5-6 bucks. the scraper works great for taking down the realy high spots and save a tone of time and sand paper. the spreaders are great for spreading bondo and cost about 1/5 of the ones that you get at auto parts stores.
(PS i got 100 grit at wal-mart. get your wet/dry papers some place els.)
IF

 

IF YOU HAVE ANY OTHER TIPS ON WAYS TO SAVE MONEY ON TOOLS OR OTHER GREAT TOOLS FOR BODY WORK...POST THEM