How to take out root of shrubs?

I am trying to change the shrubs in front of my house. I am replacing it with roses. I found good deal of roses at ALDI, they are selling each plant for $4.00. I bought yellow and pink roses shrubs. But I am not sure how to clean the root of the previous shrubs. They seem to be very firm to the ground and I do not want to hire someone to remove it for me.
Please let me know how you can you remove the root of the shrubs.

That is a good deal for roses. If you
don't know what you are doing it's best
to leave it along,you could do more harm
than good. You probably found the solution
by now,but if not, I would go to the Home Depot
and ask them for help. Maybe your neighbors can
offer some help as well.