Not to be a dick but get some real drums. Only Jesus can turn water into wine.
I've heard som PHENOMINAL drum sequencing done with really good samples - in particular, some of the Drumkit from Hell work I've heard has been good enough to the point where unless I was looking for it I'd probably not realize it was sequenced. That's a combination of two factors, though - a great set of samples with a ton of different velicity hits, and a guy using the program who really knows what he's doing.
That said... My drum sequencing is pretty poor, but at least sounds like a believable, fairly fill-devoid and overly even drum performance. This means I'm someone you probably shouldn't listen to, but since this is the internet, um...
The biggest thing you have to do here is to learn to think like a drummer. Spend some time watching videos of drummers for one, and if possible see if you can get behind a drum set. get a feel for how everything's laid out. An eye opener for me was realizing some fairly simple things to do with samples (say, a static 8th note hi-hat groove, with a crash cymbol on the 1 of ever 4th bar or something) that seem pretty logical when you're looking at a screen, are actually pretty unnatural when you're behind a drum kit. I've started to dabble on a drum kit lately (it's a LOT of fun, and my roommate has one, so why not), and in that situation maybe a better drummer could pull it off, but what feels the most natural is to actually drop the hi-hat on the 1, and use the same hand to reach over to the crash for the hit, then come back and resume on the hi-hat, such that the hi-hat drops out for the crash hit. It's little things like that, when you start sequencing keeping in mind that a drummer has 2 hands and 2 feet, so he can't really hit 5 or 6 different things at the same time, or that some motions really just are too unnatural to be feasible.
The other thing worth trying is to sit down with a drum beat, and see if you can sequence it. Try something like "When the Levee Breaks," bone simple but incredibly groovy, just to get your feet wet - you can learn a lot tryting to replicate something an actual player did.