Here are some of the more popular websites that you can check out or create a profile to self-submit (yourself) or your child on.
LA Casting: www.lacasting.com - This service is FREE when you are represented by an agent. To create a profile, it will cost you $ 9.95 per month ( or $14.95 if you add the media hosting). You get one free photo upload. If you wish to upload more photographs it's $25 for 1st photo $15 for additional photos (uploaded at same time). You also get unlimited self submissions to their casting billboard. You can also personalize your URL to your online resume (www.lacasting.com/yourname).You also get access to sides, directories, photographers, acting coaches and more. Media Hosting is $4.95 per month. This allows you unlimited uploads of your reel, clips or special skills to your profile and you can attach them to your submissions. Each piece can be up to 4 minutes in length. There is also a Pay-as-you-go feature which allows you to pay 1.49 per submission in lieu o paying for the premium service.
Actors Access: www.actorsaccess.com - There is no charge to register and establish your account on Actors Access. By doing so, you put your Profile into the Breakdown Services database which is searched by Casting Directors when they are searching the database looking for specific talent. You can optionally receive email notification of the latest roles posted that meet certain criteria in your Profile. You can upload up to two photographs for free. Additional photograph uploads are $10.00 each. You pay $2.00 per self-submission or you can subscribe showfax for $68.00 a year and get unlimited electronic self-submissions and access to sides.

Additonal places to find casting notices