Ned,
The Acc/Dist and OBV lines are useful when lining up plays, but you have to keep in mind that they only update on the chart after hours. So intraday they are useless on the chart in some respect. The counting of teh buys and sells I have found to be suspect sometimes. For example if you watch the L2s on UYG often you will see that the bid and ask often are the same due to the liquidity of that stock. Sometimes I see tons of trades go off when the B/A has no spread. Sometimes they go off green, sometimes red. So it is helpful if there is a big delta in the buys/sells, but if it is within 5% or so it may not tell you much, especially of the stock is trading within a small channel for extended periods. However, on a sub penny it can (not always) be indicitive of dilution. So if a ton of trades are being shown as buys, but the pps is not moving it can be a red flag.
For me, I use the OBV and Acc/Dist as indicators of trends over time and I will look for the reversal after a long decline in both.
Hope that is helpful