Yes, there are treatments available for the many types of anxiety disorders. They're not always successful though; mainly because people with AD often have more than one disorder or other health problems (depression, alcoholism, bipolar disorder and sleep disorders are pretty common). That said, there is definitely help and hope available...

Behavior Therapy
Aw, a shrink...? Yep. Therapy can be essential to helping someone overcome all sorts of anxiety disorders (among other things). Behavior therapy focuses on changing and controlling unwanted behaviors, usually through increased exposure to whatever triggers those anxious feelings.

So, to cure a bad phobia of mice you might start out by drawing a picture of one mouse, then ten. The next step might be to interact with a stuffed mouse before moving to a robotic one and then finally to a cute, fuzzy live one (and learning to limit how many times you say, "Ew, gross").

Cognitive Therapy
Unlike behavior therapy, cognitive therapy can help change behavior by identifying and altering unwanted thought patterns. People begin to change the way they think by separating unrealistic thoughts from realistic ones.

So, using a phobia of mice again, a therapist might have you create a list of characteristics about the rodent then a list identifying why you fear them (1. They want to hurt me, 2. They want to nibble my nose off, etc.). The therapist would then lead you through an examination of these fears (RE 1. Do mice really want to kill anybody?, RE 2. Do mice want to eat your nose or cheese?, etc.) in order to help you change the way you think about mice. See?

Many therapists actually use a combination of cognitive and behavior therapy (called CBT) rather than one type alone.

Relaxation Techniques
Relaxation techniques are exactly what they sound like--tools that can teach people to relax so they are better able to cope with the stressors that lead to anxious feelings. But it isn't just sitting around repeating the mantra "relax, relax, relax..." Using these techniques, which often include breathing exercises as well as physical exercises, can help lessen the physical symptoms of anxiety, and have a major impact on how people with anxiety disorders deal with the outside world.

Medications
There are a variety of medications that can help control anxiety disorders (they're called anxiolytics or anti-anxiety meds). Though treatments totally depend on the individual, medications are almost always used in conjunction with therapy. And they should always be prescribed by a physician.

Self-Help Groups
Yes, these groups are pretty much like Alcoholics Anonymous (AA), except they're for people with anxiety disorders instead of alcoholics. While these groups don't offer a "cure" per se, they do provide a supportive network that both empowers and comforts.

A good self-help group not only puts people suffering from a similar disorder or problem in touch with people living with the same problem, it also provides updated information and resources for participants.