Yes, when you rebuild an index the table/index becomes available as soon as the index rebuild is completed.

Statistics based on the index rebuilt are updated when an index rebuild occurs, but SQL Server also allows you to create statistics on non-indexed columns and, if left at the default, will automatically create statistics on columns the optimizer thinks will help. These column level statistics are NOT updated when an index is rebuilt thus you need to update them.

I recommend using Ola Hallengren's maintenance scripts[/url] for this type of work. Michelle Ufford also has a good index maintenance script [/url]as well.