I've actually just finished attacking a brand new Epson TX100 for exactly this purpose. ($50 brand new... why not...)
The key as mentioned before if using etching with Inkjet is that it needs to be pigment based... Epson DuraBRITE Inks are pigment based, however the Yellow and Magenta are reported to work best (or "all color black").
If you really want to build this though, I suggest setting aside a few hours and reading all of http://www.cnczone.com/forums/showthread.php?t=30951
... there is *lots* of little bits of needed info in that thread about Paper Sensor setup and "pre-print" dancing you need to account for
I've not yet etched, but i've printed - and it works great... just gotta pre-heat the boards a bit to help the ink-wetting....
Once I have finished making a "pull-through" tray instead of the carrier based board I'll be putting some entries up on my SLiDA Dev Site...
Just remember.. you need to be using *refilled* inks (MISPRO Inks are the best results one there) if using HP's or Canons. Only the Epson DuraBrite inks are Pigment based - the Caliga or whatever its called alternate Epson ink brand *wont* work. Epson is also the choice because the "PiezoElectric" print heads apparently allow them to use the pigment inks without clogging, unlike the print head technology in the alternate brands (which work, but reportedly clog easy...)
Also - really only works reliably with FeCl3 at room temp - very warm FeCl3 or other etching solutions will remove the ink much easier..
Anyway - I'll be sure to share results when I've finished...!