Started out last season myself. FWIW -- check out the equipment forum, lots of good discussion of this sort there.
Considering the day and age we chase in, some 'must haves' as I see it:
1) Get a weather radio. (simple and cheap -- but really handy)
2) Laptop (FWIW -- Toshiba makes a very durable laptop)
3) GPS -- I have a handheld. I also have GPS software you can use on a laptop. GET the laptop software. I've had good success with Microsoft Trips & Streets 2007. (title is something close to that -- look at Amazon for good deals)
4) Data solution for your laptop. You want to be able to have an internet connection anywhere. Based on my research, a Spring mobile broadband card is ideal. Why? Good coverage, good speed. Set you back 60 a month or so. Probably want to do so research in this area.
5) A good piece of software to grab radar data on. My suggestion? GRLevelX. Here's a big reason a software GPS solution is nice: (besides the big display/navigation abilities) You can output your GPS info onto your radar. You can see the storm in relation to where you are -- all on one screen. That's nice.
That's a few bucks there. Don't know about your financial situation... but if you're planning on staying relatively local, and not chasing any great distances, you could go cheap and get it done with a weather radio and good ol fashioned maps.