Take a look at: http://store.yahoo.com/semsons-inc/index.html for lots of GPS options, bundles, etc. There are lots of combos, and build your own combos from Semsons. You can find individual items with a lower price, however, there bundles usually include a free car kit, mount, etc., and discounts on the bundle packages.
For software iGuidance and Destinator have been recommended items from GPSPassion. For a very long trip I would shy away from Mapopolis, particularly if you end up having to make any deviations from your original route as you sometimes must use your PC to recalc routes (not handy at all). I am TomTom software fan myself, however, it is can be $$$ compared to some of the other SW packages.
For BT GPS on the cheap that works quite well, try the I.Trek BT GPS. $100 at Semsons. I can toss it in the back seat and still get 6 sats. Walk around with it, etc. Quite handy and excellent battery life. This is my personal BT GPS solution for use with my Palm T3, however, we have tried it with a few of my friend's PPC's (HP 2700 series and 4700 series) and it works just fine with their GPS software (Mapopolis and i.Guidance) I have been very happy since getting the BT as a switch from my wired GPS. It is super fast to acquire sats, and, as I said above, can hold quite a few while placed in places other than the dash.