Select Statement that join to different tables based on Field Contents

[Mr Initial Man]

Purpose of Post: To create a SELECT statement that returns results from multiple tables, choosing which tables to retrieve values from based on NULL fields within the main (comics) or intermediate (ComicLinks, ComicIDs) tables.
Database: MySQL 4.1.20
Database Structure: See attached image.


Rows that will always be selected:

Number, Semester, CavDaily_Edition, Comic, Drawn, Commentary, Comic_Page, Notes

Underlined fields may be null, but I have PHP code set up to handle null fields.
The field Comic_Page functions as a boolean value.

"IF Statements that alter what the select statement returns

IF Comics.RegDateID IS NULL

• NOT NULL: SELECT WeekDay, Month, Day, Year FROM RegDate join Comics on RegDate.RegDateID = Comics.RegDateId
• NULL: SELECT DateText FROM OddDate join Comics on OddDate.OddDateID = Comics.OddDateId

IF Comics.Number IN (SELECT Number FROM ComicLinks)

• TRUE: SELECT LinkTitle, Linkhref FROM Links JOIN ComicLinks ON Links.LinkID = ComicLinks.LinkID JOIN Comics ON Comics.Number = ComicLinks.Number
• FALSE: (No Select Statement)

IF ComicIDs.SoloID IS NULL

• NOT NULL: SELECT ComicTitle FROM Standalones join ComicIDs on ComicIDs.SoloID = Standalones.SoloID join Comics.ComicID = ComicIDs.ComicID
• NULL: SELECT StoryTitle, StoryNum FROM Storylines join ComicIDs on ComicIDs.StoryID = Standalones.StoryID join Comics.ComicID = ComicIDs.ComicID

How do I set up the mysql query to do this? It will be used in a PHP-based webpage, but I want to rely on PHP as little as possible so as to speed up the processing of the page.