To get some good ones , and sometime even get lucky to get new ones, go to the poker rooms and buy a rack-$100 worth of $1 chips, check them by turning them in the rack, the good ones show up real quick-keep those and then depending what values you are after, example $5 chips, go to a crap table ,ask for a stack of red, $100 worth-pick out what you want and cash in the rest. $2.50 have to be purchased from a BJ table here again look for table that has a lot of pink and ask the floor person to have dealer sell you $50 worth which is 20 chips [a stack] pick the good ones and cash in the rest.

Hope this helps and good luck.