Since you are not in love with any 1 catagory, I would recommend collecting $1.00 chips. You will find that 98% of all chip collectors have (and want) them and almost everyone will trade/swap for face value. But, what ever you decide to collect, you should kind of ballpark the cost before you start.

Attend a chipper's get together if you are close to any local club. Copy and paste this link into your broswer:
http://www.thechipboard.com/links/pages/Clubs_And_Chapters/

If you join CC>CC, there are many guides on collecting available for free.

Read and study the FAQ's on chip collecting in the link below: