Free stuff is cool...
There's loads of it on the web... just a quick google can uncover new samples here and there in no time.
5 mins on google got me here:
(forgive the dodgy URL !)
But there are tonnes of other ways to get sounds on to your Juno:
Go to http://www.rolandclan.com/library/juno-g/
and download tonnes of user built patches, and patches migrated from other Roland synths - FOR FREE !
(DO THIS - It's fab! There are some great free patches that you can load onto your CF Card or internal user patches through the standard Juno Librarian program).
Another way is if you have Sonar LE (ships with Juno) then you can download VST instruments into it.There are loads of free ones at http://freemusicsoftware.org/
I know.. I know...You don;t want to use the DAW right now... Sooooooo... What you do is download these VSTs, get a good some good drum ones, import them into Sonar, and then build simple track with one kick, snare, toms, cymbal etc. Mix that track down to an Audio track, then slice it up into individual Wav files to load into the Juno - and hey presto - new kits. I know it sounds a faff - and to be honest it is a bit - but it's all free
Oh, Do check out the Arpeggiate? kit... That's a funny one... hit the same key in 8ths or 16ths and get a different sound each time in a weird loop... How odd/cool is that? There are some good sounds lurking in there though - across the whole keyboard).
One final cool trick for tonight (don't have many left now!) is to take one of the existing kits - and build it up using multiple effects in the Juno - 2, maybe 3 effects daisy chained together by changing the structure (struct) in the MFX menu (in step 10 of my previous MFX setup "war and peace" post above). Then record a drum loop in the sequencer.
Switch to Audio mode, and create a mixdown of the drum track, and save it to your CF card.
Save your sample (with the Save / Load button left of the screen), then delete the audio and midi drum track.
Go back to the midi sequencer track where you want your drums to be, hit enter to bring the instrument selector. Scroll down the banks (guitar , strings, blah blah...) until you get to Card. Highlight Card, and you should see your drum sample listed on the right (possibly as C00010 or something). Select this as your instrument - and Hey presto..
You'll then play the loop phrase of the sample within the sequencer like any other sound. And because the Juno has Time shift, you can play it up and down the keyboard at different pitches, but the tempo will stay intact - That's quite cool - in a geeky way (think D&B;riffs at high pitch, or Super grunge drum tracks with the sample played down half an octave).
As far as setting up user kits on the Juno - I'm afraid that's beyond me! As soon as I got the TD12, I only used the kits on the Juno for tekno or programmed electric sounding kits. Sorry - I'm a bit useless there I'm afraid (hence all the other work-arounds!)
Oh look... another monster waffle from me, and after all that I didn't help with drum mapping probs.... Sorry! It's been a long day!
Have a good week and let me (and everyone else) know if Roland come back to you with some details.
Cheers for now,