I'm sorry - not in biostats personally so my opinions may not be all that helpful. But...
Are you also considering a career as a clinician (you mentioned pre-allo)? If so, have you considered epidemiology? In epidemiology, we have to have a solid understanding of biostats, but we also generally work with biological and clinical aspects as well. I'm not knocking biostats - I do know 1 person who got a phd in biostats in addition to his MD. But, in general, biostats is closely related to the mathematic theory. In epi, we cover a lot of the same material from an applied perspective (without dealing with as many proofs and underlying calculus).
When you ask about how one finds the program, I wasn't sure if you were talking about how they liked it or how they came across their program. I can't comment on the former. But, for the listing of biostats programs, check out the Association of Schools of Public Health:
http://www.asph.org/document.cfm?page=773
(I found 40 programs listed with MS, MSPH, or MPH in biostatistics)
If you want a list of MD/MPH programs (including biostats), check out AMSA's site:
http://www.amsa.org/cph/mdmphlist.cfm
And, on the AAMC website, it says that 91 schools offer an MD/PhD in biostatistics:
http://services.aamc.org/currdir/section3/degree2.cfm?data=yes&program=6
(That seems really unlikley, but that's what came up)