mmm....an indigo, a 909 & a fireworx....well sounds like you are on the right lines.....
do you actually have a computer yet??? if so is it powerfull and what kind of audio interface does it have???
assuming you do have a computer for your sequencing i personally would save up about 900 scroats for a second hand mackie 24/8
in the mean time though a 24vlz will do (about £400)
but ideally you need a desk that will do that lovely fireworx justice!!

as far as im concerned ignore those digital multitracks for our purposes (such as yamaha aww4166 or whatever it is).....- if you do want to go digital consider the yamaha o2r (or its little bro' the 03d) - about 1500 & 850 respectivly (2nd hand), but these are just mixing consoles not recorders.

You can either record back into the computer or get yourself somthing like a tascam cdrw700 (£200) and then extract that back into the computer for any post production (thats what i do)
you need to check if your soundcard is 'full duplex' - which means it can play and record at the same time, and again if it very powerful - if it is then the choice is yours....

sounds like you'll need a sampler in that set up too...if your computer is powerfull enough consider running a soft sampler...failing that get an akai z4/8 - getting pretty cheap 2nd hand....

cables wise, you will need mostly 1/4 inch jack cables and and a couple of 'Y' lead, send and return cables to get that fireworx on the aux's of your desk....