Just make sure you get quality tools - they make all the difference in the world. You'll need good crimpers for RJ11/RJ45 (a good quality ratcheting style); good punch-downs (110/66). Extension drill-bits, fish tape, fish rods, a good circle cutter and/or roto-zip for drywall cuts. fittings for Coax (RG6/RG59) - either compression or crimp; good cutters for coax, Cat5; the electrician's scissors mentioned above...
What type of work do you want to focus on? Security, HA, Audio, Structured Wiring? And new constructions vs. existing; Commercial vs. Residential?
Each one has different tools.
For the network tester, expect to spend some money; the cheapest one I've ever found that's worth anything is the Fluke CableIQ, but it's $1500. The $100 ones only test continuity, but don't test for crosstalk or attenuation, so even if the wires are physically connected, they may not work.
Also - Fox & hound for tracing; Tone & Probe - the list goes on (man I have a lot of tools for this - and I'm not a pro!).