I have property in Caldwell and Grimes Counties and oats with winter rye grass is the easiest and cheapest way to go. The mixes are ok, but unless you can fence the plot to protect it from overgrazing or plant large acerage forget it. Oats, wheat, rye, and alfalfa work well and will not break your pocket book. I run cattle and plant about 5 acres of oats without protection and they survive till late spring. I also overseed about thirty acres with gulf rye. A good clover (based on your soil ) from your local feed store would also work well with the oats. I have burr clover that reseeds itself on my clay soil. The oats work well on most soil types.

To hit a high point made on the last response.  Bur clover is a very good plant considering its drought tolerance and re-seeding ability.

What and when to plant depends on when, where and what for.  A mix of oats and wheat is a very simple, low cost way to get started...  An easy choice for falll planting... make sure you add some fertilizer. 

If your planting much acreage, make sure you do a soil sample to see what your pH and available nutrients are.  This can improve the sucess of your plot and save you money.

Other plants suchas clovers are more dependent on your soil pH and type of soil.   If your on more of a clay with a higher pH... sweetclover will do well and lengthen the season of use for your plot. Keep in mind sweetclover is not relished as well by deer... so they will mostly use it when rainfall is limiting.  Alfalfa will be very similiar in performance to sweetclover, but is more relished by deer and has a greater chance of being grazed out. A pH of about 7.0 would be ideal for alfalfa.

For warm season plots... things are a bit more difficult.  Cowpeas and lab lab are your two main options, but might have to be protected initially to keep deer from grazing to the point of destrution.  This is one reason I like to recommend adding sweetclover and or alfalfa to cool season plots... beacause they will grow into and sometimes through the summer, depending on summer rainfall.  Usually they can take more pressure than warm season peas or beans and you would only have to plow and plant once a year.