I don't know how far away any of these nurseries are from you, but take a look at HelpMeFind for the roses you are interested in.
The ones you saw listed for $15.00 may have been budded. Almost all minis are own root and sold in containers rather than bare root.
The link is for 'Sweet Chariot' but 'Gourmet Popcorn'
should be available also.

Here is a link that might be useful: HelpMeFind

Thank You very much Megroses for your help. HelpMeFind.com did not help me much as the nurseries are far away. But can you please tell me as to when should be a good time to buy miniatures? What is the avg. price for a good potted plant, say for a 1 gallon pot? I so want to grow roses and make my patio come live with color and scent!
Any help and guidance is appreciated!
Happy Gardening!

A mini in a gallon pot will cost a bit more than one in a 4" shipping pot.
Nor'East (now Greenheart Farms of Arroyo Grande)up there in northern California has great stock at a reasonable price. I've dealt with them for over 25 years and have always been very satisfied with their roses. They stand behind their roses and have quality service. I know several of their representatives personally and have always been impressed with their work ethic and willingness to do what is right for their customers.
Take a look at their website at this link.

Here is a link that might be useful: Nor'East Miniature Roses

Thanks Meg! I will take a look at the website and probably order from them. Thanks again!

Kniffing's Discount nursery in El Cajon, look in directory for phone number. Greatest place to buy any rose. Trust me on this one!

Sequoia nursery in Visalia, CA. Ralph Moore the father of the miniature rose. Tiny Pedals, check out the web, they are now in Nevada. Good Luck

Thank You BeBeRose! I will definitely try Kniffing's.