Hi Angie and welcome to RO forums.
This is good food fo bunnies.
http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=16618
Be sure to give him him enough Timothy hay so he can keep his teeth and digestive track happy. Plenty of fresh water (Lionheads have more hair from what I've heard/seen, so keeping him cool is especially important, as for all bunnies though - they really need that water when it's hot).
I keep frozen soda bottles on hand for when the temperature goes up - they really appreciate it.
They love to chew, so anything that would help in that department is welcome - I've used the lava chew rocks that some pet stores sell for chewing...some of my buns really go to town, others ignore it. Certain woods are safe for them to chew.
Old telephone directories, used TP cardboard rolls, cardboard boxes are also good for digging (the girl bunnies can dig ALOT!).
There's also a section on NIC (Neat Idea Cubes) or 'Organize It' cubes that can be arranged as kind of an extension to your cage (well, some tend to morph into castles, but that's the effect bunnies have on some of us..).
Find a good, rabbit-savy vet in your area - you'll need to get him neutered at around 4mos (unless you're planning on breeding)..even so, it's always good to have that number BEFORE an emergency hits.
When he's settled in and in a routine, also see if you can aclimate him to clipping his nails - it's easier when they're young and not full-grown.
and most of ALL - you need to post pics of your bun when you can..