So my name is taken as far as usernames and websites go so I want to replace the s in my last name with a z and just go by that. For example: Dave Herzberg instead of Dave Hersberg. (Not my real last name.)
Which then will give me… www.daveherzberg.com + usernames.
Will misspelling my name matter at all in terms of business?
Go for it. You will need an Assumed Business Name, (also called a DBA—Doing Business As). Or form an LLC using the new name, which might be a good idea for liability.