If you already know what you are doing there's the Cobb Access Port and the UpRev reflash tools and software. There may be a few others.
Not sure if those can also datalog fueltrims, if not, you'll also need something that reads CAN BUS so if you start making any changes in closed loop, you can address fueling issues more precisely (or, I suppose, turn closed loop off entirely...).
Allgedly no one can seem to tune VVEL, but I'm fairly sure my buddy who uses UpRev can... not sure on this one.
EDIT: This is a good link with info on the various maps uprev can edit. It's for a 350Z, but my guess is that the ECU's make use of similar maps (e.g., the so-called high and low detonation ignition maps).
http://www.my350z.com/forum/mid-atla...al-period.html
If you are a newbie to tuning, start with a good text on the basics -- here's one I highly recommend for beginners and even folks with some hands on experience
Amazon.com: Engine Management: Advanced Tuning (9781932494426): Greg Banish:…
You'll probably also want to pick up a wideband (e.g., AAEM UEGO) and of course set aside lots of road and dyno time.
Learning about EFI sytems can be daunting... if it seems too complicated, locate a qualified tuner in your area and go to him.