For people with Celiac Disease, eating at restaurants is a challenge. Unless you are sure that a restaurant has a good understanding of Celiac Disease and cross-contamination, I suggest avoiding eating at most restaurants. A good way to be social and still eat safely is to bring your own food. I suggest calling a restaurant ahead of time to let them know you have Celiac Disease, and would like to bring your own meal to be reheated there. You can usually give the meal to the waiter, have them reheat it in the microwave, and serve it on a plate when the rest of your group is served (this is a great strategy for weddings or catered events).
Often, when you call to discuss this with the chef, restaurant staff may offer you some gluten-free alternatives. This is a great time to work with the staff and design a gluten-free meal, but be wary of hidden cross-contamination from less-than-knowledgeable staff. Although it may seem like you're a difficult customer, restaurants are often happy to accommodate you, since you'll create a lot of repeat business and bring your friends back with you.
Many chain restaurants like P.F. Chang's and Outback Steak House have gluten-free menus available online. Any time you're ordering gluten-free, be sure to speak with the chef (not just your waiter) and clearly establish your needs. I suggest doing this over the phone beforehand if you think you may feel awkward or picky discussing this at the table with your guests present. You can also order gluten-free dining cards to give to the staff when you order to identify hidden sources of gluten and explain your condition (available from www.triumphdining.com - there are many other free versions online).
Any time I order gluten-free food at a restaurant, I leave a generous tip to compensate for additional work the staff may have done (such as checking with the chef repeatedly) and to encourage waitstaff to be responsive to diners with dietary needs. When I've had a good experience at a restaurant, I call or write a note to thank them. At a recent visit to Jacques Imo's, a restaurant in New Orleans, the staff recognized me from previous visits and brought out a free gluten-free dessert (crème brulee) for everyone at the table. Celiacs are very good customers when we communicate our needs and are grateful for the opportunity to dine out safely!
In the worst-case scenario, a restaurant may be unwilling or unable to help you, or may be hesitant to let you bring your own food. In this case, I suggest keeping a gluten-free protein bar or snack in your pocket or purse, ordering a nice glass of wine, and enjoying the company instead of focusing on eating. It helps if you've eaten beforehand, to avoid convincing yourself that the food may be safe. Also, remember that alcohol lowers your inhibitions, so be sure to plan ahead if you may be around food.