You can directly use the Tool in this link = http://http://roitco.vmware.com/
You can read the detail description of TCO in here = http://www.vmware.com/pdf/TCO.pdf
This is some simple User Guide on How to use the Tool :
The VMware TCO Calculator was developed jointly by VMware, Inc. and ex-Gartner ROI / TCO experts from Alinean, Inc. to provide a Total Cost of Ownership (TCO) and Return on Investment (ROI) analysis for implementing VMware solutions to virtualize your IT environment including datacenter server infrastructure, testing/development labs and desktops.
You can quickly assess potential cost savings by completing five easy steps:
Step 1: Fill out a Simple Survey Questionnaire
Answer a few questions about your company (such as the type of industry you are in, and location) and which of the VMware solution sets you are most interested in:
1. Data Center Server Consolidation Cost Savings (Using VMware Infrastructure 3)
2. Virtual Lab Automation Benefits (Using VMware Lab Manager)
3. Desktop Control and Manageability Cost Savings (Using VMware Virtual Desktop Infrastructure VDI)
For each selected solution area of interest, you will be asked five to ten additional questions about your existing assets such as the number of servers or desktops you intend to virtualize, and about cost reduction opportunities such as current server management, management activities, storage and other metrics.
Default metrics are provided for all of the questions based on Alinean research regarding your specified industry and location. These defaults can be reviewed and adjusted to best match your own unique metrics. This is the only information that is necessary to get a quick estimate of potential cost savings and return on investment (ROI)!
Step 2: Customize Assumptions
The tool uses over 200 additional metrics to help calculate a credible and achievable costbenefit / ROI analysis. Each of the 200 metrics is set using default assumptions based on the metrics you provided on the questionnaire regarding your industry, location, assets and current cost opportunities, and using industry average and third party research. All of these values are preset using this research, but can be easily reviewed and refined by clicking on the “View/Edit Default Assumptions” link on the bottom right corner of each solution set on the Questionnaire page. You can then review each default assumption and make adjustments to
precisely reflect your current environment and actual costs as needed. For a quick analysis, you can skip this step, revisiting the default assumptions for refinement later.
Step 3: Review Total Cost Savings and Return on Investment (ROI)
Click on the “Next” button to see your customized cost savings, comparing your current (As Is) total cost of ownership (TCO) over the next three years (managing a non-virtualized / business as usual environment), and the cost savings and business benefits estimated for a virtualized VMware environment. Key metric and financial improvements are summarized at the top, while specific details for each solution are provided in the tables, graphs and charts. For each selected VMware solution, you can click on the solution name in the table or the tab to view cost savings / benefit, investment and ROI details for VMware Infrastructure 3, VMware Lab Manager and VDI independently. Continue reading VMware TCO / ROI Calculator User’s Guide