That's something you and your agent should have dicussed already.
There's no absolute answer to this. Certainly once a week, just for a status update. Perhaps twice a week.
Early on, you should be getting more frequent reports, since the first few weeks are going to be critical in generating interest and activity. You should be getting feedback from showings, from broker opens, from regular open houses (if you've had any), from your agent's marketing efforts, and more.
A website hit report is meaningless. Even for web-based businesses, such reports are notoriously unreliable. Besides, whose website is this? Your listing should be on many, many sites--from your local MLS to Realtor.com to Trulia and so on.
Call your agent up today and request twice-weekly reports.
Also, your agent should have presented you with a marketing plan. Make sure that your regular reports go through the list of the different marketing efforts (postcards, direct mail, newspapers, fliers, signage, open houses, etc.) to confirm that the promised activity is actually being done.
Hope that helps.