I have trouble getting cell coverage on my Verizon cell phone in my
basement in Nashville, TN.  I have heard of devices that boost signals
in hard to cover areas by placing an antenna on the roof or outside
the house.  I found one at http://www.smarthome.com/9625.html but it
only works with 1900 MHz PCS-based phones and as far as I can tell,
that will not work for Verizon phones here.  I am having trouble
finding these devices online and finding which one has the best
"reviews."  I would love to hear about a few different
devices like this and/or one that seems to be right for what I need.

The little cell phone signal boosters from ebay work great. You simply
stick them behind your battery. I didnt think they worked at first but
after i tryed one i noticed a vast improvement. Also you cant go wrong
with the price :
http://cell-phones.search.ebay.com/signal-booster_Cell-Phones_W0QQcatrefZC12QQfmcZ1QQfromZR8QQfsooZ1QQfsopZ1QQsacatZ15032

Midmac

if you have no signal now 
you will need a repeter, as for models and reviews, last I checked
only one company had one that would work for verison, it was a few
thousand dollars, they had directions on the website so that you can
figure out if it will work in your location, I almost purchased it
when they put in a new tower and I did not need it.

if you have marginal strength now,
sometimes you can find an aftermarket antenna for your phone that
works better than the original.
most motorola phones will see a vast signal strength improvement with
a nice antenna, samsung usually shows little diffrence.