This will take you to a Spreadsheet of my 40 Most common used sources:
Check Out Roderick Cannon's impressive Bibliography with Geoff Hore's Updates
The outstanding Resource for PDFs of pipe music manuscripts (I Specifally use his for Sutherland's Pastoral Manuscript) Ross's Music Page:
Ceol Sean is an incredible collection of Old Bagpipe Settings you can Download as PDFs Note that the Link is to a wayback machine capture, and may not be perfect.
I find myself using this resource more and more lately, the Traditional Tune Archive,
Not perfect, but better than thesession.org for finding manuscript sources.
John Glen's Early Scottish Melodies is a Great Resource to look over, especially since it is Glen's Collection I use most often to find Tune Settings.
John Walsh's Collection of Caledonia Dance Music published in the 1730s.
A Collection of Scots Tunes, William McGibbon, Published 1742-1746 NLS COPY
Click here to Download PDF (link from Ross's Music Page)
Oswald's The Caledonia Pocket Companion volumes 1-7 Published 1747ish
Bremner's 1757 ( I think) Scots Reels Collection
Bremner's 1769 Scottish Reel Collection
Aird's selection of Scotch, English, Irish, and foreign airs Vol 1
Aird's Selections of Scotch, English, Irish, and foreign airs Vol 2
Aird's selection of Scotch, English, Irish, and foreign airs Vol 3 &4
Aird's Selection..Volume V & VI
Neil Stewart's Collection of Scots, English, Irish and Foreign Tunes (1780s)
Edward Buntings A General Collection of the Ancient Irish Music
(transcriptions from the famous 1792 Harpist Gathering First Published in 1797)
Edward Bunting's 1809 General Collection of the ancient music of Ireland
Edward Bunting's 1840 The Ancient music of Ireland
O'Farrell's Pocket Companion: first published around 1806 (Volume 1 & 2)
George Forrester's Pocket Companion for the German Flute 1817
Donald MacDonald's First Tune Collection of Piobaireachd, with the most common
Dance tunes from his day at the beginning (1820)
Donald MacDonald's Collection of quicksteps, strathspeys, reels, & jigs (1828)
Angus MacKay's Piobaireachd Collection, First Published 1838
Including Hereditary Piper Info and competition results dating back to 1781
Angus MacKay's The Piper's Assistant, First Published in 1843
Davie's Caledonian Repository