The following information relates to the 2008 02 19 13:30:59 UT fireball seen over north-west USA and British Columbia. For UK readers, I should make it clear that we are talking about Pendleton, Oregan, USA and not Pendleton, Lancashire (sadly)...
That must have been quite an experience.
I think the short answer to your question is that no one knows for sure where resulting meteorites would have fallen, but you are certainly in the right general area. Any new and acurate eye-witness reports, particularly from so close to the likely fall area, would clearly be most valuable. If you know of any witnesses of the event who have not yet filed a report, then please ask them to do so. They can contact me, at the address below, and I'll point them in the right direction.
In addition to the information provided above, the most reliable information I've seen is from the Cascadia Meteorite Laboratory, Portland State University.
Here's what they say...
Scientists including Dick Pugh and Alex Ruzicka at the Cascadia Meteorite Laboratory (CML) at Portland State University are sorting through dozens of phone calls and emails sent in to the laboratory to determine whether the bright meteor (fireball) seen over a large region of the Pacific Northwest yesterday (February 19) at around 5:30 AM Pacific Time produced any meteorites and if so, where they might be found. Based on eyewitness and seismic data, it appears that the meteor probably did produce meteorites (rocks on the ground) northeast of Pendleton in Oregon. Eyewitnesses from Oregon,Washington, British Columbia, Idaho, Montana, and California saw a fireball moving generally northwest to southeast. This trajectory is generally consistent with video of the fireball taken from Portland, Oregon and elsewhere. Sonic booms sufficiently loud to rattle windows and startle people awake were reported in Hermiston and Pendleton in Oregon; at these locations the fireball was bright enough to turn night into day for a few seconds. Less intense sonic booms were reported in Union, Oregon. At least one and possibly two major break-ups of the meteor occurred shortly before it hit the ground, producing dozens of tracks with three major ones apparently corresponding to large pieces of material. Some eyewitnesses said the natural display reminded them of a â€œRoman Candleâ€