Personally, I'd skip the electronic scale and go with a good beam type. RCBS and Redding make good ones. Electronic scales are too erratic for my taste.

Obviously you'll need dies for each cartridge. A full length die and seater die for each will get you started. Then you might want to consider neck only sizing for certain cartridges, so you might want to add a neck die later.

In no particular order here are some other items you'll need and my preference for each:

Reloading Manual (Nosler, Hornady, Sierra, Lyman, etc....)
Calipers to measure cartridge length
Primer tool to seat primers (I prefer the RCBS hand held unit)
Case lube (I like Imperial wax)
Powder funnel (Satern makes the absolute best IMO)
Bullet puller (inertia type)
Case trimmer (Wilson)
Case mouth deburring tool
Primer pocket cleaner (I like the Sinclair primer pocket uniformer for this)
Case neck brush
Powder trickler (Redding)
Case tumbler (not totally necessary, but I wouldn't want to be without mine)

I think that covers the basics. There are other optional tools that some of ususethat are designed to help get the utmost precision and accuracy out of handloads and you can decide later if these are needed depending on how serious you want to get with this.

Also, here's some other sources for reloading tools and supplies:

www.sinclairintl.com (my favorite)
www.grafs.com
www.lockstock.com
www.midsouthshooterssupply.com
www.midwayusa.com