The information in this response is specific to Minnesota and may or may not be applicable to your area.

Pampas grass (Cortaderia selloana) is a large perennial grass native to Brazil, Argentina, and Chile and is not hardy in Minnesota. It will survive in zones 7b -10. Although the plumes are beautiful there is danger of damage to passersby from contact with the very sharp, sawlike edges of the leaves.

You may want to consider Miscanthus sinensis (Siberfedher, silver feather miscanthus). It grows 6 to 8 feet tall with large silvery flowers. There is a wonderful publication available through the University of Minnesota called "Ornamental Grasses for Cold Climates." It provides detailed information on these grasses along with beautiful photos and cultural requirements. It can be purchased at your local Extension office or through the live link below:
http://www.extension.umn.edu/distribution/horticulture/DG6422.html

Here are a couple more links to information on ornamental grasses:
Ornamental Grasses for Minnesota
http://www.extension.umn.edu/info-u/plants/BG464.html

Landscape Grasses
http://www.sustland.umn.edu/maint/grass.html