Hello and welcome to the neighborhood!
If you are here on the forums you are only a click (or two) away from nearly every frequency you could ever want. Just click on the "Database" tab on the blue bar at the top of this page. From there select PA and then Delaware County. There you will see radio usage broken down by service, Fire/EMS, Police, Municipal, etc......
Police in Brookhaven (27 Cars) and Upland (26 Cars) both operate on Delcom's S(ector)-1 and M(utual)-1 as well as ALPHA talk-around (can only be heard very close by).
On the fire side Brookhaven (Co.52) and Upland (Co.57) both operate on Fireboard's Channel 3. They may also use Ch. 11 thru 14 Fireground channels (also local area only listening). All County Fire/EMS Depts are dispatched on both low band (46.48) as well as UHF (508.2375) I find the UHF sounds better here in the Western County. Brookhaven's EMS as well as Crozer's Medics operate on Med-B.
On both the Police and Fire systems the channels are shared with several other town's depts so get familiar with the local numbers that I listed above and are listed in the WIKI.
Your scanner doesn't handle PL/DPL tones (used to isolate users on a common freqency) so you will (may) see a little conflict every once in a while due to both Med-A and Med-B having common freqs with fireground channels 13 and 11, not really a big deal though as the fireground channels are simplex and only need to be turned on if you are at or near a scene.
Once you go to the database, heres Delco Delaware County, Pennsylvania (PA) Scanner Frequencies and Radio Frequency Reference and gather all the freqs you are interested in you will want to click on the "Collaborate" tab on the upper left under "County Home". This will take you to the WIKI and will allow you to then click on the Delaware County page. This is where you will find all the Police and Fire districts and station numbers that will make monitoring more enjoyable. Heres a direct link Delaware County (PA) - The RadioReference Wiki
Good luck, I hope this helped some, check back with a progress report.