Get the UVB bulb right away. You don't need to pay for a custom setup, just get a reptiglo 5.0 or similar and put it on the top of the cage and you will be fine.
It's good you're looking into real plants - that will help with the humidity. Make sure you get non-toxic plants - clyde may eat them! Common good plants for Chams are Ficus Benjamina, Pothos and Schefflera - get some plans and vines that bring him within 6" of your UVB and Basking lamps.
You can make a drip setup yourself just by poking holes in the bottom of a paper cup and putting it on top of the cage.
There are excellent articles on plants, husbandry, resources, etc at
www.chameleonnews.com. In addition to the help you are getting here at HC, there is a very active group of Chameleon owners over at ******************. The moderators are much better and helpful here, but for chams in particular, there are some extremely knowledgeable and helpful folks on that forum.
Greg