Publishers
- Metropolitan Museum Of Art (Harry & Abrama) 1
- Metzler & Co. 1
- Michael D. Dobson 1
- Michael Hale 1
- Michael Hardcastle Publications 1
- Michael Imhof Verlag Gmbh & Co. 1
- Michael J. Elsden 1
- Michael Joseph 31
- Michael Joseph Ltd 1
- Michael Moon 2
- Michael Neugebauer Ltd 1
- Michael O'Mara books Limited 6
- Michael Russell 1
- Michael Russell (publishing) Ltd 2
- Michael Stanfield Holdings 3
- Michael Stanfield Holdings Ltd. 2
- Mid Glamorgan County Libraries 1
- Middleton Press 12
- Midland 1
- Midland Automobile Club 3
- Midland Bank 1
- Midland Counties Publications 3
- Midland Educational Co. Ltd. 2
- Midland Publishing 28
- Midway 1
- Miklo 17
- Milepost 1
- Military Book Society 2
- Military Heritage Press 1
- Military Mode Publishing 1
- Mills & Boon 2
- Millstream Books 2
- Milner 1
- Milner And Sowerby 1
- Minister Of National Defence 1
- Ministry Of Agriculture Of The Republic Of Iraq 1
- Ministry Of Industry And Primary Resources Brunei 1
- Ministry Of Trade And Industry 1
- Miracle 1
- Miss N. Littleton 1
- Missionsbuchhandlung 1
- Missouri Bureau Of Geology And Mines 1
- Mitchell Beazley 6
- Mitchell Hughes and Clarke 7
- Mitchell Information Services Inc. 1
- Mitsubishi Motors Corporation 1
- Mixing 1
- Model Aeronautical Press Limited 2
- Model And Allied Publications 3
- Modern Promotions 3
- Mondo 1
- Monmouth District Council 1
- Monmouthshire Antiquarian Association 1
- Monnow Press 3
- Monogram Aviation Publications 1
- Montvert Publications 1
- Moody Press 1
- Moonraker Press 1
- Moorland Publishing 7
- Morgan & Lester Publishers 1
- Morning Sun Books, Inc. 1
- Morris & Company 1
- Morris Motors Limited 3
- Morrison & Gibb Ltd. 3
- Morrow Junior Books 1
- Moss Rose Press 37
- Motivate Publishing 3
- Motor Racing Publications Ltd. 33
- Motoraces Book Club 4
- Motorbooks 3
- Motorbooks International 13
- Motorbuch 1
- Motorbuch Verlag 3
- Motta 1
- Mountain House 1
- Mouton De Gruyter 1
- Mr. Edwin Stooke 1
- Mr. Norman Rose 1
- Mrp 3
- Mrs. Eugenia Stanhope 1
- Mtp Press Limited 1
- Muinck & Co. 2
- Mulder & Zoon 5
- Mullet Press 1
- Mullock & Sons Limited 1
- Munksgaard 1
- Munshiram Manoharlal 1
- Murfett Pty. Ltd. 1
- Murray's Children's Books 5
- Murrays Sales & Service Co. 6
- Mursia 1
- Museet For Varde By Og Omegn 1
- Musei Vaticani 1
- Museum Of Art 2
- Museum Of London And The Council For British Archaeology 1
- Museum Of London Archaeology 1
- Museum Of Modern Art Oxford 1
- Museum Press Limited 3
- Museum Publishing Co. 1
- Mx Publishing 2