I started collecting pins after my visit to WDW in 2004 and buy what I like the look of, some are limited editions and worth quite a bit of money, others are in sets, it just depends what I like.
I am quite a serious collector and I find the pins from UK sellers (on ebay) to be really expensive and the postage ridiculous. I will not pay £1.50 or even £2 for a pin that weighs nothing so I actually buy my pins from the States, from a really great guy in California, it is ALWAYS cheaper than buying in the UK. The postage for each pin from the States is 50cents! and because it's so much cheaper I buy about £30 at a time and get loads for that price.
If you just want the odd pin or two then the UK sellers on ebay are great but I buy lots at a time and will always buy from the same guy in the States.
If you want his details then just PM me and I will get them for you.
I collect whatever I fancy, my DD collects Minnie pins and my DS collects Mickey pins!
I hope you have fun with it, I love my pins and have great memories every time I go through my pin bags!
Here are a few of the ones I have!