I still use a Sony Pockettrack, which is over 10 years old now, for practice and field recordings. There are better options available these days , with better mics, better storage and better computer integration.
I recommend something like this: a portable digital stereo recorder with built in condenser mics. I think about it this way: for better or worse, the technology is above the standard used when Bream and Segovia recorded much of their early work, so what you play is what is heard, more or less. And they're generally easy to use and convenient, as you can just press record and go. Not a whole lot of engineering knowledge required.
A quick search at Musicians Friend or your preferred retailer for a Tascam, Zoom or Sony portable field recorder should give you more than enough options to choose from. Sometimes with these devices the simpler is the better as long as the mics are good. Which they are in most every case.
"Music is a higher revelation than philosophy...
[and] is the mediator between the spiritual and the sensual life." Ludwig Van Beethoven