Based on my years of personal experience, JMBulion (and their other website, silver.com) is always cheaper than Apmex anyway. And JMB also pays you more when you sell coins back to them. Apmex does indeed have a bigger selection and flashier website, but that's not as important to me.
http://www.silvermonthly.com/jm-bullion-reviews/
However, Apmex has a great digital investment that's backed by physical, and is as easy to purchase as buying ETF shares online:
www.onegold.com
This might be the best way to get something immediately if you can't find a retailer with coins in stock. Plus it's much more convenient to sell the digital asset in a few clicks, compared to shipping your physical coins back in the mail.
Disclaimer/Caution: I am not buying right now at these prices, and would not necessarily recommend it to a newbie. The better time to buy was when the price was lower, like only months ago when silver spot price was under $20/oz.