InDesign's Find Font and/or Find/Change (set to Search: Document) commands are the fastest way to change text formatting throughout a document. Both automatically search and replace in Master pages as well as document pages, and both can find text formatted with a missing font and change its typeface to one available.
Tiplet: Bet you didn't know that Find/Change's Find Format Settings, revealed by clicking More Options in Edit -> Find/Change, could find missing fonts, did you? If missing fonts are called for in the document, their names appear in brackets at the very end of the dropdown menu of typefaces in the Basic Character Formats panel. If you don't see yours, try choosing any font from this menu, click in another field, then go back to the dropdown menu and look at the bottom ones again. It's like a mini-Refresh … your missing fonts should now appear.
Find Font and Find/Change Format are also great for changing all usage of a Type 1 or TrueType typeface to an Open Type version. A lot of clients moving to InDesign/InCopy workflows are doing this to their publication templates to make cross-platform work easier. (The same Open Type font can be used as is on both Mac OS X and Windows 2000/XP.) And many other places are moving to Open Type to take advantage of OT-only features:
Here comes the BUT … Neither Find Font nor Find/Change Format can access style sheet settings in InDesign CS. So while the text that's already in your document might be completely updated, there's a good chance some of your Paragraph and Character style sheets still call for the unwanted typeface(s). Blech!
Running that initial Find Font or Find/Change only does half the job. If you click inside some text that you've run the Find/Change on, you'll probably see a plus symbol appear after the text's linked style sheet in the Styles palette. The plus symbol here indicates local formatting "on top of" style sheet formatting, because InDesign is reading the new typeface as local formatting applied to every single character.
Not only that, but as soon as you enter any new text and apply the original style sheet, bang, you're back to where you started: an unwanted typeface in the doc.
Redefine Style to the Rescue
If you think you'll have to open each of your 200 style sheets to manually check for and change typeface settings, don't worry. You're forgetting about that friendly little command in both the Character Styles and Paragraph Styles palettes: Redefine Style.
Redefine Style is the plus symbol-eradicator. The Plusinator, baby. You use it to tell InDesign, "See this local formatting right 'chere by my text cursor? Change the specs of the original style sheet to match it." InDesign looks at the modified text formatting, updates the original style sheet to conform, and voila, the plus symbol disappears. What was local formatting is now "native," base style sheet specs.
Bonus: All other text in the document formatted with that style sheet updates to the new specs in unison, but retains any *other* sort of local formatting (e.g., All Caps) it might have had.
So … armed with this knowledge, you can combine Find/Change or Find Font with Redefine Style to do document-wide AND style sheet-wide typeface changes at the same time.
The key is to make your font changes one at a time. You want InDesign to *search* the entire document, but for this technique, you want it to *replace* instances one by one. That way you can decide if you need to redefine a style sheet while you're at it. So, in either Find Font or Find/Change, after selecting the fonts you want it to find and replace, click the Find First button and then stop and look at what it found.
Did just a few characters get selected (found)? It's either "true" local formatting (not tied to a style sheet — in that case, click Change and then Find Next) or the font is part of a Character Style applied to the selection (follow the same general instructions for redefining a paragraph style, which follow.)
Did an entire paragraph (or more) of text become selected? Bingo, you've likely tracked down a paragraph style sheet that needs redefining. Leave the changed text selected and look at your Paragraph Styles palette. If you see a single style sheet selected with a plus symbol after it, choose Redefine Style from the palette.
[If you're not sure it's the font change that caused the local formatting, before you choose Redefine Style, undo your font change (Edit -> Undo) and click in the paragraph. No plus sign? Go ahead and Redo the font change, then Redefine Style. There was a plus sign even before you changed the font? Redo the font change but don't Redefine. This is one style sheet you'll have to open up and check manually for typeface specs.]
I know it sounds a little complicated, but it really isn't. You're just updating style sheets as you're replacing fonts. And since redefining a style sheet updates all text in the document linked to that style, often you only have to do it once — it's like a Change All, and the missing font name disappears from your choices in Find Font or can't be found with the next Find/Change.
If the missing font is still listed after a Redefine, it's probably used in another style sheet. Click the Find Next button and repeat the same check-for-plus-symbol/redefine-if-necessary steps.
Run through this routine for every missing font. When you're done, you have a document that's good to go, inside and out: Master pages, document pages, and style sheets.