I thought about this in trying to establish a digital media center at my company. Bottom line - for a small starter group (read only me and equipment for one or two) for hardware (PC's, drive space & peripherals), software (gotta run fully licensed), cameras (you will need at least two, one for backup - both pro-sumer at least), assets (royalty free stuff - music, graphics, photos, stock clips, etc....) and a starting batch of consumables (DVD's, tapes, labels. cases, stuff like that) figure anywhere from $50,000 at the low end to around $100,000 to be more realistic.
That's just my opinion - your mileage may vary. I am not a professional videographer nor do I play one on TV.