If you bring your cell phone with you to Davis, getting connected to the grid is very easy. All you have to do is go to one of the local mobile providers such as AT&T or T-mobile and get a pre-paid account. The prices should range between $35-$45 a month for unlimited talks, text and internet.
Both providers mentioned above are located downtown at:
T-mobile 110 F St c
AT&T 140 F St
Of course, other providers can be found in Davis as well. If you do not have a cell phone, you can find one in any of these stores, but a much cheaper option would be to buy it on Amazon