I'm a long ways from Denton, TX, but if you do get a user group started, you will probably find that once a month is too often. You can probably pull it off if you keep the meetings very informal. If you have more formal meetings with presentations, you will find that having one every two months is hard enough, or perhaps too hard. The users group in Portland, OR, used to have meetings every two months but has fallen back to once a quarter.
I just googled Denton. Since I drive 80 miles to get the Portland users group, I find it a little odd that you don't just drive to Fort Worth or Richardson. In fact, I find it a bit odd that there isn't a single Dallas-Fort Worth users group. Maybe Texans are more parochial then Oregonians.