From my recent personal experience I’d say… start with standard position: mic standing about 30-35cm in front of the 12th fret.
About getting new equipment… I went for a large diaphragm mic with switching patterns (cardioid/omni) because I also wanted to use it for purporses other than just recording the guitar… but if you want it mainly for recording the guitar you’ll probably do fine with a single cardioid pattern mic. Also, from what I’ve read, a small diaphragm mic should be good too… (I’m willing to try one out if I manage to borrow a decent one from someone)
If you buy a new mic, from my recent search about it, I’d say T-Bone’s probably have the best price/quality ratio. But from what I’ve seen from other users comments here on the forums I wouldn’t go for one of the cheapest…
The one I got (SC1100) I think it’s pretty good. For a few more bucks you can get the SC1200 which should probably be a slight improvement over the SC1100. On the cheaper side you have the SC600 for which I haven’t been able to find any reviews, so can’t tell if it’s worth buying or not… All these have cardioid and omnidirectional switching patterns.
On the cardioid only range I’ve heard very good things about the SCT800, but that’s a bit more expensive than the others above. There’s also the cheaper SCT700, which I haven’t heard anything about, but I guess it’s probably an older version of the SCT800.
On the small diaphragm range of mics I won’t recommend anything since I haven’t search anything about those…
I think all the mics I mentioned above have XLR connector and need phantom power, that means you can’t connect then directly to the computer… You’ll need a preamp or some other interface that will provide the phantom power and other than xlr connector that you can connect to the computer (either line-out or usb). Line-out will be dependent on the quality of the soundcard too… USB won’t.
The T-Bone usb micplug is not bad for the price… but after you listen to one of those mics connected through an ART usb dual pre you won’t want anything else hehehe (well koz will praise about the peavey mixer boards… hehe but they’re big ).
Another small detail to be aware about getting one of these mics… They’re usually big and heavy and don’t stand up on their own… so you’ll need a mic stand… (you should be able to get a fairly decent one for about 25 euros or so)
Advice from someone who went through that process recently… be aware and prepared to read/search a lot and change your mind many times hehe There’s so many options available that it won’t be easy to make a decision… Also be aware that there are no miracles and, in a general way, the better quality you want the more you’ll pay… You’ll need to find that sweet spot between your budget and how much quality will be good enough for your ears.