Everyone's advice is great, but I do want to add something regarding male vs. female tiels.

I have a male cockatiel, and a female cockatiel, and both are wonderful, sweet birds with such great but different personalities. Popcorn (my male) is very outgoing, very 'spunky', curious, LOVES to sing/dance. He's a CLOWN and can keep you laughing for hours. He loves giving people kisses and making a kissie sound along with it. He walks and dances to 'gracefully' like a king, and it is hilarious. Males tend to whistle/talk/vocalize more than females, in general.

Muffin, my female, is also a wonderful bird. She's very much a 'velcro birdie', and LOVES to cuddle, snuggle, and get scritchies on her head/neck/everywhere. She loves rubbing her head against my cheek, and will sometimes fall asleep doing that. It is SO sweet. She tends to be more quiet than Popcorn, and only makes noise when she needs or wants something. She's extremely loving. Unlike Popcorn who seems to love people, in general, she's more into 'one person'. She loves the whole family, but she really loves me......follows me around the house, cuddles with me, and calls me. I 'think' females are like that...quiet and shy, and bond most to their favorite person. Males tend to be more outgoing. Of course it depends on the bird too, but in general, this is what I've noticed.

I *love* both my birds, and love having both a male and female, because they are so different, but both SO sweet. I guess your decision on the gender is really up to you. The cons for males might be too much singing/talking/whistling if you don't like that, but Popcorn only whistles in the morning, and I *love* his voice, so that's a pro for me. Cons for females could be egg laying and egg related problems, but that too, shouldn't be a problem if they are in good health and fed a well balanced, nutritional diet.

I personally love tiels, males and females. They make wonderful pets. Good luck!