Here's a good brief list to start you with:
http://www.redearslider.com/res-guide.pdf
You'll want a separate UVA bulb ( a regular light bulb) and a UVB bulb ( buy at petstore) until your tank is much larger...over 50 gallons i think because the multi bulbs are too warm for a smaller amount of water and you'd have turtle soup
You want a filter that is rated to clean a fish tank 3x the size of the tank you buy.
Don't buy the special "turtle tanks" they have a filter hole in the side and you can't fill them all the way up so your turtle outgrows it faster.
And don't buy gravel, you'll soon see that turtle's eat or at least try to eat everything

and you don't want him getting impacted on gravel.
Good Luck.