My university is in Oklahoma and most companies are in east coast and west coast in the US. I am a bit worried if a PhD will be worthy from an average university with poor location. Should I apply to a college where there is a bunch of industries around?
Far more important than location is the quality of the program. You can get some measure of the program's quality by looking at the job placement of recent graduates. If they are making it out to the companies you are interested in, then you should be fine. If all the graduates are staying in-state, you will probably want to look to a different program.
The location of a school is far less important than its reputation in the field. In particular, a school may have a top-10 department in some fields, but have only an average reputation in general.
A good employer who knows his field will know which schools are good and which are not. Location close to industry will not matter as much, so long as you can get on the radar screen of potential employers. This is where your contact network and mentors will be able to help you negate any potential disadvantage of being far away from the traditional job centers in your field.