ok just because your asking this i'm going to assume you don't know exactly what you are doing here. that being said this is what you want to do:
clean very well
some use soap and water or use brake clean
do not touch IT with your bare hands after it'* are clean.
then use some adhesion promoter
then a few prime coats.
all high temp paints should be used and should work fine, just pick your own color scheme
use a final(alot more then one coat) clear coat for a gloss and protective coat.
if you do a good job it can come out like this
i personally really like this paint from duplicolor and have used it all over my ride including the calipers:
if you do this then you'll want to paint your valve covers too obviously so everything matches and looks nice here'* a link for j00: How to Paint a Valve Cover on a Car | eHow.com
<--i do recommend using a few good coats of a high temp clear coat before you reinstall for obvious reasons.
oh and if this is your 1st time follow the directions on the can to a T and do a bunch of coats of paint and clear. the more clear the deeper the shine loooks and helps protect it ALOT more.
edit: the smart thing to do if goto a bodyshop and have them spray it for you so it matches your outside paint btw. and while you're doing that just throw a bunch of other pieces you want painted as well in. it'* really not very expensive.