2. Any ski will do. If your czars are good enough for you on alpine, then you're fine on telemark. The whole concept of a "telemark" specific ski is just marketing
3. Bindings... There are two different standards of bindings for two different standards of boots. The new NTN boots and bindings are more expensive ($600-$800 boots, $350 bindings... and you're not likely to find cheep used boots any time soon). The NTNs are stiff, have a free-pivot tour mode, and are step in. They are also heavy and work better for experienced, stronger telemark skiers. The other standard is 75mm. This is your standard telemark gear and you can find great used stuff everywhere. Boots: Garmont EnerG or Voodoo, Scarpa T1s, Crispi and Black Diamond also make decent boots. Bindings: Hammerhead or Black Diamond 01 (I have and love my BD01s for backcountry touring/skiing). If you can find a pair of the Bomber Bishops they're the best for charging hard but have no tour mode.
4. Starting: get the set up, ski a couple laps on them on your hill. Don't even worry about making a telemark turn. Just get used to the set up.
5. Find someone who teles to take you out. A couple of over-the-internet pointers. Keep your weight even on both feet and on the balls of your toes. Think like you're squishing a bug under your toes. Stupid beginner mistake: make sure you're dropping your uphill knee. Lead change at the apex of your turn and settle into your stance as your coming around.
haha i was in thesame position 4 or 5 years ago when i first started telemarking. when i first started i rented some untill i knew i would stick with it. then i started going into the back country and skiinning when i was good enough. now i do both alpine more but deffinatly try it out
which is more appealing to you? telemark skiing, or skiing in the backcountry?
if its the latter you can buy AT bindings (marker dukes) and skins and you will be able to travel uphill easily, and rip just as hard as you can regularly.
for skin size you just need to make sure that you buy skins that area as long and as wide as your skis and then cut them to the shape of your skis (you can have a shop do that for you too.)
For any Backcountry skiing, it is essential to take a level 1 avalanche class, get all of the appropriate gear (tranciever shovel & probes) and know how to use them.
avalanches aren't something to fuck around with, and its easy to make a fatal mistake if you don't know what you are doing.
finally if you can find someone in your area who also backcountry skis in your area, see if you can get them to show you around. Its very helpful to start with expierenced people. i'm sure you can find people on here or especially TGR
alpine trekkers work with any normal alpine binding. whatever you currently have on your skis would presumably be compatible. they basically click right into your existing bindings, then the heel part raises, similar to tele but stiffer, so you can skin uphill. then when you are ready to ski down, i believe you take the trekkers out, click into your normal bindings, and get your shred on. (disclaimer: i have not actually used trekkers- i have actual AT bindings- but i have fiddled around with them at the store and they look pretty sweet)