It should include a little set of Allen keys & wrenches that'll get you started, otherwise a set of pliers, a small sharp blade (X-acto knife, Leatherman tool, etc.) and some CA glue for the tires should be all you need

To add to what gweed mentioned about a servo, a good truck servo should be metal-geared and put out around 120oz-in of torque at 6 volts. The Hitec 625MG is a popular choice, and I had good luck with the Futaba S3305. I think both units go for around $40

You probably don't need an M11 radio either, way more buttons than you'll know what to do with for offroad. I have a Futaba 3PM 2.4GHz FASST radio and for probably half the price of an M11 it does everything I need and then some

Best bang for the buck on a battery charger nowadays: DuraTrax Onyx 230. Charges NiCd, NiMH, LiPo, Li-Ion, LiFe A123, doesn't require a separate power supply, pretty easy to use, costs about $80