We just put in a new core network with all-new switches, along with an extensive wireless network, as part of our new building addition program. In order to determine the best locations to place wireless access points (13 total), we needed to do a site survey. I researched several software tools, and most of them were expensive to the point of being out of our price range ($1500 or more in general). Eventually, I found a relatively new piece of software I found called VisiWave  that fit the bill perfectly, and was inexpensive enough for our budget: $549 minus a 20% non-profit discount (contact them and ask for the discount code). It also integrates with the Wi-Spy  spectrum analyzer (I didn’t find it through Jason Powell but he has two good posts I found recently about it: Part 1  and Part 2 ) if you purchase it, to map channel interference as well as its primary job of mapping existing access point strengths/weaknesses.
VisiWave is easy to use, even without the Pro version (the SO version, for Software Only, is the one we purchased, and is significantly less expensive). You need a floor plan of some sort for your facility (whatever area you’re going to survey). Import this into the survey half of the VisiWave software (the other half is a separate reporting application for creating a report from the data collected by the collection tool), and then walk around your facility clicking at key spots where you’re located on the map on the laptop you’re carrying with you (a Pocket PC is an option as well, but we used a laptop). A time-saving feature lets you switch to a mode where you can click on your current location, walk at a steady pace in a straight line, and click your ending location, and it will distribute the data points collected evenly over the line you walked. It sounds simple, but it saved me a lot of time! The VisiWave website has good instructions and example reports.
I’ll most more example of the survey report and such in the future (our initial survey was last October), but this has proved to be a very useful tool that we can use over and over again, rather than hiring someone to do a site survey once. I did the survey before placing new access points, but I haven’t had time to re-survey since we installed the new APs, and there are four I haven’t installed yet. We do have very good coverage based on the 9 that I have installed based on the original survey already, however! I’m looking forward to the final survey and report, and to fine-tuning based on those results. Our grand opening is the week after Easter next month. I may or may not have the public internet stuff set up by then (using a Nomadix  AG 3000 ) but the equipment will be there for when I figure out the software and the filtering solution to use, so it should be ready shortly thereafter.