I realize this is a really late response and you've probably solved it by now, but it may help others too. I had the same issue with my phone after installing a CyanogenMod rom, where I couldn't even boot into recovery. You will need to find the stock rom package for your phone on your computer and download the file. You will also need a way to flash the rom via usb. For example, a free program called Odin works for Samsung devices. Regardless of what program you use-- "jumpstart" your phone into download mode:
- Take off cover and pull out battery
- Hold volume up + down + power button
- Plug in usb cable that is connected to the PC (kind of tricky to do)
- Phone should buzz once, displaying warning triangle that says "No OS installed" or something like that. Release buttons.
- Open the program for flashing the rom, and follow directions specific to that program to flash your stock rom
This is how I recovered my Galaxy S Blaze after soft-bricking it sometime last year. Hope it helps!