Joann,
Yes, we certainly do have a billet gas door available for the Dodge Dakota.  But you didn't specify what style of replacement billet gas door that you were interested in.

On one hand, we have a stainless gas door cover.  It is essentially a thin disk of polished stainless steel that is laser cut to the size of your Dodge Dakota's factory gas door.  The stainless gas door cover comes with a double-sided adhesive on the back and just sticks to your factory gas door.  And yes, the double-sided adhesive is plenty strong and will last a long time.  Most of the badges and trim on your Dakota are attached the same way.

Another product available is an actual replacement billet gas door.  Basically, you just remove your Dodge Dakota's factory gas door and bolt this one on in its place.  Most units install with two simple screws and anyone with hand tools and a free twenty minutes and do the switch. 

To suite everybody's needs, these units are available in many different finishes;  chrome, polished aluminum, brushed aluminum, brushed chrome, black, and polished stainless steel.

Some replacement billet gas doors for your Dakota (and most other trucks) also come with locks installed to keep would-be gas thieves at bay.