I also live in the desert, but in cali. What I have found works best is this. I put the seeds in little ziploc bags sandwiched between a wet papertowel. Put that on top of my water heater (or any good heat source) for 2-3 days. Then just plant them in the ground once I see good germinating going on. That way the seeds germinate nearly instantly, and they'll poke through the ground within a couple days. Saves a lot of time waiting for them to come up.

I've tried it with peas, pumpkins, cucumbers, and corn and it works great for all of those.

I prefer to direct seed if at all possible, which where I live (arid 7,000 feet elevation) is everything EXCEPT tomatoes, peppers, eggplants, basil, and artichoke grown as an annual, all of these simply due to the long season they require.

By direct-sowing I can be confident that as soon as germination occurs, the conditions are right for steady growth unhindered by acclimitization delays or transplant shock.

Purplemage, it sounds like your problem may be soil temperature, not lack of moisture since two waterings daily should be plenty. You might want to grab a soil thermometer and compare the temps to the chart below. As you can see,
even the low desert is probably not quite ready for some of the warm season crops (corn, beans, tomatoes, peppers, cucurbits, etc).

On the other hand, I'm already getting germination of my cool season veggies at 7,000 feet.

A final note: row covers, floating covers, and fabrics do speed germination and retain moisture, but can be more work and expense of course. I mulch right over the larger seeds (corn, peas, beans, cucurbits), and leave the smaller one's uncovered at first.

Here's that list...
Soil Temperature Germination Ranges for Select Vegetables
TEMP (� F) PLANT
45�85 cabbage, kale, broccoli, collards (germinate well at 85, seedlings prefer 45�65)
35�80 lettuce and most salad greens (at more than 80, germination rate drops 50%)
35�75 spinach (optimum 68)
50�85 onions (optimum 75)
45�95 radishes (optimum 85)
50�85 beets, Swiss chard (optimum 85)
60�85 beans, snap and dry (optimum 80)
70�85 beans, lima (optimum 85)
40�75 peas (optimum 75)
60�95 corn (optimum 95)
65�82 tomatoes (optimum 80)
60�95 peppers (optimum 85)
65�100 cucumbers, melons, squash (optimum 80�95)
From: Market News, March 1995.