Although most new fly fishers associate fly fishing with trout, anglers have been fly rodding for black bass since at least the 1800s. That's when railroaders increased bass distribution Westward by dumping fingerlings into water ponds along the ever increasing miles of new railroad track. At present, there are more bass within reasonable driving distance of anglers than trout.
If you are throwing small flies at bantam-weight pond bass, your trout/sunfish-sized 5 weight outfit will work. Larger bass flies require something like an 8 or 9 weight setup. For pulling bigger fish out of nasty cover, you may want a 10 weight stick.
Rods and Reels
Bassing with a fly rod involves a lot of casting, so the rod is the most important part of the outfit. A reasonably functional fly rod should have at least as many guides as feet in length (an 8-1/2 foot rod should have 8-10 guides). Information on the length and fly line weight should be printed on the rod, just forward of the grip. If the rod says it takes a #8 fly line, that's what you should have.
Bass fight dirty and don't often allow you time to get them on the reel. For that reason, and because you won't be using especially light tippets anyway, the reel is not as important as the rod and line. Most reels come with information suggesting what weight lines they accommodate.
Fly Lines, Backing and Leaders
Make sure the fly line weight and the line rating on the rod match! The vast majority of your bass fishing -- even with sinking flies -- will be done with a floating line, and that is where you should start.
After you've mastered all the possibilities of a floating line, you may find yourself buying an extra spool for your reel and purchasing a sinking or sink-tip line. Tapered lines fish more easily than a level line. Lines that manufacturers label "bass taper" are special weight-forward tapers. These work well for delivering a bug beyond your false-casting distance. Double taper lines lend themselves to accuracy in circumstances where you are fishing at a pretty constant distance (working a shoreline from a boat), picking the fly up, and laying it back out with no false casting.
You should have dacron backing behind the fly line to fill the reel, but it won't come into play when fighting a bass.
Most fly leaders are tapered, but a precise taper isn't as critical in bass bugging as it is in dry-fly fishing. Because of the rough cover you'll be dragging your leader through, it IS important that the leader material will handle abrasion. This aspect is more important to this type of fishing than small diameter. Many expert bassers are using fluorocarbon tippet for this reason.
The stereotypical bass bug is the classic cork popper. Available in a variety of shapes and dressed with feathers, hair or rubber legs, these bugs derive their designs from early bass lures. Other surface "bugs" are constructed from chewier materials like foam or trimmed deer hair. During the summer, it's not a bad bet to dig through your trout box for a grasshopper pattern. As with conventional bass fishing, the surface bite is only a fraction of the action. Streamers (baitfish imitations), upsized trout nymphs, wet flies and jig-like bottom bouncers are all highly effective. If you tie your own, you'll find yourself installing weed guards on your flies to minimize hang ups.
Modern float tubes and kick boats have their origins in homemade 1800's contraptions developed by bass anglers who did not want to be limited to wading or walking the shore line. These highly portable fishing platforms open lots of new fishing water, help you escape the crowd and give you a better angle of presentation to your quarry.