What kind of seminar? I'm sure you're talking about the bootcamp. What bootcamp did you attend? Most training providers will make you practice in their lab. If you want to build your own lab then Jhaddix and Laz3r have posted wonderful tutorials to build a virtual test lab. You can get them here:-
Network pentest lab setup    
Pentest Lab: Web Application Edition

You may also like to read the following article by Daniel V. Hoffman- Review: CEH Via Self Study. It's a little old but should be enough to get you in the right track. More recently awesec has posted a review of CEH iClass. You can check the study methodology he has adopted.

Also, check the threads in the CEH board http://www.ethicalhacker.net/component/option,com_smf/Itemid,54/board,2.0/ 

see my reply in your other topic. if you attend a bootcamp you should be fine. dont worry your pants of, just keep a clear mind and you will do fine. Good luck!