Unless you plan on having runs longer than 300ft, fiber shouldn't be necessary. It will cost considerably more for little benefit.
I would suggest doing a MDF - IDF setup. Basically put your main rack (MDF) in the office area, then 300ft away put your IDF somewhere, either in a cabinet or up on the wall. Unless you have computers that are further than 600ft from the MDF, only one IDF should be necessary. Then just link the switches between the IDF and MDF through their gigabit uplink ports using Cat6 (since a warehouse is probably a high noise environment, Cat6 will likely be better than Cat5).
Unless the computers are being used to transfer large files locally, there is no reason to use gigabit switches in my opinion. Get 100Mbit switches with gigabit uplink ports to link them together.
Are you planning on using IP phones or cameras as well? If so, get some good quality POE switches, or at least one to power your AP's. I like these POE switches made by Panoptic: http://www.panoptictechnology.com/pse-24-poe-switch/
They're pretty powerful and they can run well in fairly high-heat environments. They supply 15watts to each port as well. Panoptic also makes adapters for non-poe devices as well, so you can power almost everything via POE (which is handy for remote management since you will be able to log into the switch remotely to reboot devices as necessary): http://www.panoptictechnology.com/network-smart-adapters/
As for routers and APs, I would highly suggest taking a look at the Mikrotik devices: http://routerboard.com/
You can't beat the performance and reliability they offer for the price. A little RB450G will have more than enough power for you as a gateway router. Then a few RB711UA-2HnD boards should be perfect as your APs. If you can get away with it, I would suggest no more than 3APs in the warehouse since there tends to be issues with noise in large metal buildings.
To answer your other questions as well:
Will this setup eliminate routers and patch panels?
No. You will still need a gateway router and I would highly suggest using a patch panel at each location with switches. The patch panels aren't completely necessary, but they make it look like nicer and help with organizing your cables.
What about a redundant VLAN switch in case of switch failure?
Sure, redundancy is good if you can afford it. You can do multiple cable runs between switches, just be sure to enable STP on them.