G
| Publisher | Website | ISBN prefix |
| Gallup Press | www.gallup.com | 1-59562 |
| Global Travel Publishers | 0-939895 | Go! Comi! | www.gocomi.com | 1-60510, 1-933617 |
| Green Integer | www.greeninteger.com | 1-55713, 1-892295, 1-931243, 1-933382 |
| Green Candy Press | www.greencandypress.com | 0-9638129, 1-889539, 1-931160 |
| Grove Press
Atlantic Monthly Press Grove Press Black Cat Grove Press Open City Books |
www.groveatlantic.com | 0-394, 0-8021, 1-5584,
0-8021, 0-87113 0-8021 0-8021 |
| The Gryphon Press | www.thegryphonpress.com | 0-940719 |
| Gürze Books | www.gurze.net | 0-936077 |
H
| Publisher | Website | ISBN prefix |
| Hg2 | www.hg2.com | 0-9547878, 1-905428 |
| Haus Publishing | www.hauspublishing.com | 1-904341, 1-904950, 1-905791, 1-906598 |
| Hawthorne Books | www.hawthornebooks.com | 0-9716915, 0-9766311 |
| Haymarket Books | www.haymarketbooks.org | 1-931859 |
| Healthy Travel Media | www.patientsbeyondborders.com | 0-9791079 |
| Helter Skelter Publishing
The Black Book Company |
www.helterskelterpublishing.com | 1-900924, 1-902799, 1-905139
1-902799 |
| HJ Kramer/New World Library | www.nwlib.com | 0-915811, 1-932073 |
| High Times Books | www.hightimes.com | 0-9647858, 1-893010 |
| Hoberman Collection | www.hobermancollection.com | 0-9729822, 1-919734, 9-9916763 |
| Holy Cow! Press | www.holycowpress.org | 0-930100, 0-9779458 |
| Hopscotch Press | 0-9625155, 1-885355 | |
| Hundreds of Heads | www.hundredsofheads.com | 0-9647858, 1-893010 |
| Hunter House | www.hunterhouse.com | 0-89793 |