i'm not sure what you precisely mean by "event".
usually, finding an error involves knowing what time stamp to look for and finding that problem in the access and/or error logs.
many OS distributions include helpful tools, so you might want to explore that avenue.
i haven't tried it, but you might want to look at wtop and logrep.
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i typically use general-purpose command line text processing tools to explore the log files like (e)grep, cut, sort, uniq, wc, etc.
i also wrote a script i use to do certain types of analysis.