Check out this recent thread on brake shims

http://forums.teamestrogen.com/showthread.php?t=5681

Or you could replace the levers with something that has a reach more suitable for your hands.

A simpler idea that might (or might not) help is to move the lever up or down on the bar (this requires untaping the bars, disconnecting the brake (and maybe gear) cables, loosening the lever with an allen wrench, moving the lever, retightening, and retaping. After you manage to grab the brake lever, is the distance of the lever from the bar when you have the lever compressed to brake still too far and uncomfortable? Simply lengthening the brake cable 1/4 inch may help (clamp the brake callipers to the rim with a 3rd hand tool or strap, loosen the cable binding nut on the brake, pull a bit of cable through, and retighten). If you can brake fine after grabbing the lever, maybe you will be OK if you practice the lever grab by letting your arms move wider and your wrists rotate so your hand is to the side of the bar and only your thumb behind it when you grab.