Similar plugin to GuideGuide for illustrator
You don't need GuideGuide. You can use the canned Illustrator features.
- Draw a rectangle to match your outer dimensions.
- Choose Object > Path > Split Into Grid.
- enter the rows and columns you want and any gutters between them and click OK.
- Choose View > Guides > Make Guides.
You can also tick the "Add Guides" option to automatically create guides which align to the rows and columns.