You can buy Google Mini for your enterprise that comes with hardware and software. When you buy Google Mini then Google send you a machine that has all software installed. You can place this machine in your office and configure to index your file share servers, Intranet, Internet and other portal.
This is a trim down version of Google Search Appliances that we bought in our office.
The cost vary based on number of documents you want to index. To have capability of indexing about 50k documents for 2 years you pay about $3000. After 2 years you can keep the same box and continue to use it or can replace it with the new hardware and warranty.
I know about Google Mini for long time but writing about it now as I am working on Google Search Appliance and I wanted to document that Google has a mini version of Google Search Appliance (which is Google Mini) that you can use.