Q:

How can I really get rid of henbit?

Every year in early March it seems I have a ton of henbit, (lamium amplexicaule), in my yard (Southern US, zone 7, bermuda grass).  Not just around the edges, it's all over the yard.  By May/June it dies off, but it amazes me that the yards next to mine don't have the same "infestation" of the weed.  I end up being the first house around me having to mow to cut it down and make the lawn look presentable.
The local various lawn services say they can get rid of it and make my lawn beautiful, but I'm still not willing to pay $55/application for something that I can probably do myself for $25.
Is there a proven method that I can use to get rid of henbit fast and not see them ever again?

A:

If you want to keep henbit out of your lawn, you will need to apply a pre-emergent very early in the season (in the south, as early as February) to prevent it from germinating. An organic option may be "corn gluten" which also inhibits the germination of annual seeds.  
Many commonly used chemical lawn fertilizers already contain pre-emergents to fight annual weeds - they are called "weed and feed" products.  This may be why your neighbors are not having the same issues with the henbit that you are having - they may be using one of these. 
In the meantime, you can probably spray a broadleaf weed killer, or spot treat with something less noxious, to cut back the amount of henbit seed that your already growing henbit plants will be leaving behind this growing season.  

