You have to use the vimdatastore provider to access your datastores.
This is documented in the vSphere PowerCLI Administration Guide, which is installed on the PC where you installled PowerCLI.
You can use the 'normal' cmdlets to navigate, test and create folders.
ls # Will show the top level
cd MyDatastore\MyFolder # Navigate with the 'cd' alias
test-path MyOtherFolder # Check for the existance of a folder or file
mkdir test # Create a folder
I hope this helpsBlog: http://lucd.info | Twitter: @LucD22 | PowerCLI Reference co-author: http://tinyurl.com/hkn4glz