Not everyone has an arranged marriage, in fact if you're in a big city, it's probably more common for your marriage NOT to be arranged. As far as I know, marriages aren't arranged from childhood, but as kids become adults, their mothers may get antsy and start looking around for suitable matches. This can take a few different avenues...
Turkish newlyweds... don't they look happy?!
1. I've seen women go door to door in a neighborhood that looks like a good socio-economic match for their son/nephew. They knock on the door and ask whoever answers, "Is there a girl in your home?" I don't know how often this method actually works out. I mean it seems to me that a girl's mom would have to be amazingly desperate to consider marrying her off to a family that goes around like salespeople trying to peddle their son.
2. Here's a common one: If a friend or relative is getting married, then the moms, grandmas, and aunts check out all the eligable young maidens while they dance at the wedding or engagement party. This way the prospective bride is somehow connected to you. She's a friend of a friend or a relative of a relative. It's easier to trust people who are connected to you.
I went to an engagement party once. All the women were separated from the men, and the girls had an amazing dance party (I took pictures, but they were lost when our computer crashed... drats!). All the younger unmarried girls got up and danced, and they really put on the moves. Meanwhile, the older women sat back, watched, and picked out a few prospects to ask about. I think it usually goes something like this: The boy's aunt asks who that pretty little thing in the red dress is. After she's told, she finds that girl-in-red's aunt and asks her about the possibility of a union. If things look positive, then the boy's aunt will tell the boy's mom and dad, who then find a way to check out the girl.
3. Many mothers of eligible bachelors are just ALWAYS on the lookout. I've been asked multiple times if I know any sweet American girls for someones son. I've gone into shops with single friends and watched older women approach my poor girlfriends (who are just trying to buy sausage or parsley) and tell them about their son.
Bubbly cup of coffee
Whatever the method of finding the prospective girl, once she's been spotted, the boy's family makes an official visit to check her out. I'm not sure exactly what happens on that visit except that the boy looks at the girl, and his mom looks at how clean the house is (she has to know if the girl is a good house keeper) and everybody tries some Turkish coffee that the girl has brewed up in the kitchen. It has to taste just right and have lots of bubbles. I'm sure I would fail at this part. I am a horrible Turkish coffee maker. Good thing James' family didn't know that!
I think that the next step is often for the boy and girl to go out once or twice just to make sure they can tolerate one another, then once all the okays are given a wedding is planned.
I have one friend who met her husband-to-be during a 20 minute Ramazan visit (she was a relative of his sister's fiance). He came back to her house with his parents for a taste of frothy home brewed coffee a few days later, and they were married about a week and a half after that. I think they skipped the go out alone and make sure you can tolerate one another part. Apparently it was SUPURB coffee and they were pretty eager to get hitched.
Our neighbor's son, on the other hand seemed to put off his wedding forever. He was well into his thirties when his mom finally coerced him into an arranged marriage. He met the chosen girl and seemed to like her alright, but really dragged his feet about getting married. I think he was engaged for at least 9 months. Before the engagement his poor mother's main goal (and she let everyone she ran into know it) was finding him a bride. She asked me for names of friends, and thoroughly grilled me about every girl who entered my home. She told me about meeting girls on busses or in shops and trying to lure them into a wedding with her son.
Arranging a marriage can become an all-consuming venture.