I can't vouch for the items in it, but an earlier submission gave the following as the best starter kit:

http://www.popularmechanics.com/outdoors/sports/watersports/gear-up-the-best-snorkeling-tech#slide-1

Here's the items on amazon (no affiliate links):

• Mask
• Fins
• Snorkel

Buying all of these will blow your budget out of the water though.