Im having trouble writing drums out for my guitar riffs and fills?

i write the drums digitally in nuendo. i can't play drums worth a crap. i can kinda play the beat with my hands im looking for but when i write it in it just sounds not right. im tried changing tempos. recording the riff first then adding drums. and all im good at is writing straight double b stuff and blast beats and punk drums. but im trying to do stuff like metalore riff with simple beat, i just feel i got to many snares and kicks back to back with not enought resting between hits. also, is there a site that writes out some cool drum fills i could use? i suck at fills too.