I just bought one of the kits from ecigsmokestore.com and I'm working on simple, single flavor eliquid right now. I have a couple of mixes in mind though...
Status Update:
After a 5 hour trial run here's a few thoughts I have.
1. Using your roommate as guinea pig is invaluable...
2. Practice measuring out liquid in your syringes/droppers prior to starting.
3. 3ml bottles are awesome for experimenting.
4. Those little bottles of flavoring pack a punch. A single drop of pmegranate will rock your socks.
5. Be careful washing those syringes out...the printed lines might just wash off >.<
6. Wear your gloves, there will be dripage.
7. Your PG/VG/Nic Juice might not drip too well straight out of the bottle, a syringe with a hefty needle on the end of it will help here.
8. Different guage needles are your friends

9. It makes sense that you'll want to test out your creation before claiming success. You might want to do so with an atty that has been broken in...you also might want to have something handy to wash the current flavor out with...unless you've been dying to find out how Mint Pomegranate Cappuccino tastes

10. I transfered my flavorings from the nifty glass bottles to plastic dropper bottles, it just seemed easier that way.
11. If you are doing this without the EJucie calculator...then you are way cooler than me.
12. Don't feel too bad if you totally screw a batch up, if I've learned anything tonight...it's that there's going to be one hell of a learning curve with this. It's all trial and error, so be creative. If a flavor doesn't work out the first time don't write it off, a good imagination goes a long way...well it goes until that particular flavor runs out anyway
- R0b