Arab food is a somewhat ambiguous term. Normally it refers to food from the Eastern Mediterranean refering to Lebanese, Syrian, Palestinian, and Jordanian cuisine. The reason I point out this distinction is because food from the Arabian Peninsula is quite different and isn't as internationally recognized.
Eastern Mediterranean Arab cuisine (Lebanese, Syrian, Palestinian, and Jordanian) incorporates a lot of spices and herbs but it is by no means "hot" as is the case of Indian food for example. The spices used in Arab food are very flavorful but not hot and certainly will not burn your mouth. Syria's second largest city, Aleppo (Halab in Arabic) is very famous for spices used in Eastern Mediterranean cuisine.
The secret to Eastern Mediterranean Arab food is olive oil, lemon juice, and garlic (either chopped of powdered). These three ingredients are essential and are used in just about everything whether vegetables or meats.
Because the Eastern Mediterranean region was under the rule of the Ottoman Empire together with much of the Middle East, North Africa, and Southeastern Europe for more than 600 years, the foods from this entire region including Turkey and Greece share many similarities. So if you go to a Lebanese restaurant and then a Turkish restaurant, you will find many similarities. The differences will be certain refinements such as the types of spices used and the amounts of spices used.
Food from the Arabian Peninsula states is quite different in that it is heavily influenced by South Asian cuisine because of the historic trade routes with South Asia, so it can be pretty spicy. Most of the Arabian Peninsula never was under Ottoman rule and was isolated from much of the rest of the world, so it developed its own culture and own foods.
If you want the best Lebanese/Syrian/Palestinian/Jordanian food in the USA and arguably some of the best in the world, visit Dearborn, Michigan. There are several really great restaurants on Warren Avenue and Michigan Avenue. I know I gained weight after spending just 5 days there a few weeks ago...
"Generosity is giving more than you can, and pride is taking less than you need." - Khalil Gibran