I love recording other people playing acoustic.
I hate recording me playing acoustic...placement...record...listen...move....record...listen....scream.
But because a microphone is the best way to capture the most natural sound of an acoustic - it is annoyingly worth the pain.
I am in a fortunate position to have some good gear - but like most, my first microphone was a 57 (going into a line 6 UX2 -remember those?) - so if you currently only have a 57 then go for it - lots of decent sounding recordings have been made with it!
I would use a mic and pre of pretty much any quality over going direct for recording...though for convenience I continue to try every possible option/new tech development.
I've tried the popular profiles mentioned here, and I think they are better suited to live - as the sound is that of an electro-acoustic. They do sound great live or in rehearsal, and there are profiles out there of an ACUS One amp that I think are the most natural sounding.
I've tried the 3Sigma impulses in my DAW, (the martin and the taylor) and they sounded worse than going direct - and I was really disappointed - as I thought they might be brilliant and was looking forward to Kemperising them - like Pete Thorn did with the Helix.
It would be worth saving up to buy a quality microphone, or stereo pair - and then a quality preamp. You're going to be playing guitar all of your life (I hope!) and being able to get your home recordings as close to professional is really, REALLY exciting, rewarding and bloody expensive. If you can't sacrifice, save and then spend on your most favourite thing to do, what can you? If it is regular trips to Amsterdam, then fair enough.
I either use a large diagram condenser (U47 or Pearlman TM-1), or a pair of condensers (Little Blondies, MC930s or KM84s) in an XY or separated to body and neck if the player is percussive or wants more string articulation due to their style. They run into two Portico 2 channel strips and then out to stereo CL1Bs doing 0.5/1.0db compression on the loudest parts and then to a PCM92 for some beautification. It sounds lovely!
For going direct for quick recordings/demos then straight into a channel - take out the mud between 200-400Hz, cut the lows out around 80Hz and add a little shimmer with a shelf at 10KHz...all that can be done with an EQ plugin if needed.
You might be surprised at how good your guitar can sound going direct if you remove the frequencies you dont like - rather than trying to add something you think it needs.
Good luck, make sure you value and get more excited about the quality of the performance over the quality of the gear; and I would be happy to help if/when you do record something to give you some friendly advice Greg