The quickest way I've found to integrate MKTO with Outlook is through Sales Insight. It allows Inisght users to do many things, inlcuding sending Marketo emails from both the CRM and Outlook.
Here is the deep dive on Sales Insight. Held within you'll find general info about the product and its Outlook intergration.
A word of warning though: Outlook integration requires Admin access.
Hope that helps!