If you want to do your own, beldecal.com makes water-slide paper that I've used and had good luck with. The inks may not last as long as professional, but the major ink manufacturers have addressed this some and make longer lasting photo inks now. The decals I've made (on the bikes I still own) over the past 3 years still look good.
To do the white lettering you'll either need to:
1. put the decals over white paint, or
2. use the "white" decal paper they sell, and you'll have to trim the edges very carefully as any edges you leave will be white, too