Hi, Ed.
Which version of Quicken are you using?
I'm running Quicken 2007 Basic in Vista Ultimate x64.
By lending money, you have created an asset called a "receivable". Whether you call it a Note Receivable, a Loan Receivable, an Account Receivable or something else, it is an asset to you. It IS cash flow - out, of course - and will some day generate a cash flow in, you hope.
In Quicken, there are several ways to get to the Account List; +A may be the quickest. On this screen, click Add Account in the menu bar at the top right. On the next screen, click This account is not held at a financial institution. On the next screens, click Asset under Property & Debt, then name your new account (Receivable from John Smith?), and enter zero as the "ending balance on the [prior] statement".
Yes, you could consider it a negative liability, but Asset is a better term.
Since Quicken's Investment Accounts are designed for marketable securities, your best choice for a real estate investment is an Asset Account. You probably will want a separate account for each property, but I'll leave that discussion for later - and for other readers here who are more experienced than I in using Quicken to manage and account for real estate.
RC