Located some great guides whose goal is to assist the reader through the process of planning a SharePoint Server 2010 infrastructure by addressing the following:

Step 1: Identify the Requirements

Step 2: Apply the IT Policies

Step 3: Define the High-Level Architecture

Step 4: Design the Web Server Infrastructure

Step 5: Design the Application Server Infrastructure

Step 6: Design the SQL Server® Infrastructure

Step 7: Identify the Optimization Opportunities

These guides are available for download. The first guide takes the architect through an easy-to-follow planning and design process to successfully create a SharePoint Server infrastructure that is appropriately placed, sized, and designed to deliver the desired business benefits, while also considering the performance, capacity, and fault tolerance of the system.

http://download.microsoft.com/download/5/B/C/5BC966BC-47D8-41DF-95F2-FA9A2D816258/SharePoint%20Server.zip

For more information go here: http://technet.microsoft.com/library/gg581794.aspx

This guide provides a clear comparison of SharePoint collaboration technologies across on-premises, standard hosting, and dedicated hosting scenarios. The guide can be used as a framework for evaluating the technical feasibility of Microsoft SharePoint Online and determining which SharePoint delivery model best suits the organization’s needs.

http://download.microsoft.com/download/5/B/C/5BC966BC-47D8-41DF-95F2-FA9A2D816258/SharePoint%20Online%20-%20Evaluating%20Software-plus-Services.zip

For more information go here: http://technet.microsoft.com/library/ee354215.aspx

Am building a presentation summarising these guides for a future blog coming soon!