Riders Now just published a good article on lowering your motorcycle by changing the saddle, with a nice resource list. See Lowering Seat Height: Options for changing your motorcycle’s saddle by Pamela Collin.
It doesn’t cover shortening the suspension, but this oldie but goodie in the June 2001 issue of Motorcycle Cruiser magazine has a good article on that topic – for cruiser style motorcycles: How to lower your motorcycle’s profile and seat height by Jerry Smith.
For advice on lowering a dual-sport, such as a DR-Z400 or KLR 650, there are no end of forums and vendors who will help you through the process of lowering the suspension — about 1.5 inches — and shaving down the stock seat to get the bike down to a 32" seat height.
Remember, it’s not a beginner’s bike if you can’t get both your feet flat on the ground, so before you go tiptoe, practice on a bike that’ll keep you stable and safe. In case you’re not convinced, here’s a link to the Top 5 Reasons to Start on a 250cc Motorcycle. And while you’re at it, take a look at 8 Great Beginner Riding Habits, too.