HELP How to create SF2 files?

[AndrewSimon]

I am pretty sure this can be done but I have no clue where to start.
I would like to sample my real instruments.
Record notes at several velocities and save them as wav files.
Then I need a program to assemble all these samples and export it as a SF2 file?
How? What? How much?
I would prefer a fast an easy way if possible.
Any help would be great.
I read somewhere that Crystal can do something like this but I am not sure I understood correctly.

[chico.co.uk]

You can apparently do it by hand in text files, but it's a real pain. This looks like it could be quite a decent little tool if it lives up to it's billing;

http://www.soundfaction.com/alive/

You could also look at Awave, particularly if you're interest in transforming things like Battery or DR008 kits to soundfonts and vice versa