Bike suggestions, advice, cautions, etc?

Bike suggestions, advice, cautions, etc?

I'm looking to buy a bike. I'm hoping it will replace my car almost completely, so I'm willing to spend some money on it. My price range is about $500-$1000. I figure that's what I would spend in gas, oil changes, and other car maintenance this summer. I've been fitted on Kona, Specialized, Trek, and LeMond frames. I know nothing about bikes, so I'm not partial to these brands, necessarily, they're just the ones the local bike shops have readily accessible. I plan to use it for commuting to work and for errands, but I would also like to use it for exercise. A road bike or a cyclocross would be best suited for my riding. What brands/features/etc are worth the money, and which ones are just flare? Are any easier to repair than others? What about buying a bike on ebay? Is there a "poor man's guide to bike shopping" guide out there somewhere? I have a bike, but it cost me $70, I've already put $200 worth of work into it the season before last, and it needs about $200 more work now. Besides the thought process that it might make more sense to put $200 towards something new.... it's time for an upgrade. If I'm going to be on this thing for 7-14 hours/wk commuting (hopefully about 25hrs/wk total -- I want to start training myself for road races), it needs to be comfortable, and fit me better than S/M/L/XL. I planned to use my current bike all season before, and it's just not comfortable enough for me to keep up with that.
Hold your noses…. she’s a bloomin!

Hold your noses…. she’s a bloomin!

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Mystery plant

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Bag for gift bread: Update

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WOOT Seedlings!!!!

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sign of spring