My Dorema awning skirt has rubber peg ladders attached as standard so I just use tent pegs to hold them firmly to the ground. The only real issue is if we are pitched on a slight slope but then the ladder design is beneficial as you can still stop any flapping of the skirt even if there is a slight gap.
You can buy rubber ladder straps independently but an awning skirt has to have the loops and ladder straps sewn in when new as they are permanently fixed and can't be removed.
If the skirts are made of the tough woven PE type material (like Cabanon tent skirts are made of), you can use thin steel pegs through the skirt to hold it down. If the skirt is smooth PVC, then it would just rip out with pegs, so you would need to use Clingons to clip onto the edge of the skirt & peg the guy rope out.
Regarding the second link from birdman101, most awning skirts already have brass eyelets in so you can use those sort of pegs which are better actually as they can be pulled out of the ground much easier than tent pegs. However, to the OP, I would suggest that if you don't already have any eyelets in your awning skirt to purchase some self clipping eyelets (shown in birdman's first link) and fix them in yourself. Problem solved and probably the cheapest way.