From Pattaya, Thailand to Battambang, Cambodia: a long story about a convoluted and mostly boring process that I hope will help someone in the future. (Trip taken on 2016_02_06.)
I wanted to cross the border at Ban Pakard/Prum (Thailand/Cambodia). However, I could not find a direct bus from Pattaya to Ban Pakard. Even the tour companies that make visa-border runs only go to Poipet or Trat. The solution was to go first to Chanthaburi and then (the Lonley Planet's suggestion) to find a minibus to Ban Pakard. The hard part was finding a minibus to Chanthaburi.
I first went to the big bus station on Pattaya Nua to ask around. A German(?) guy with a badge suggested that I go to the Num Chai appliance store (just north of Pattaya Klang road, at Soi 49 and Sukhumvit Highway, south-bound side) and find the bus station there. I went and couldn't find anything and then it got dark so I headed home. Across the highway (on the north-bound side) from Num Chai is a gas station. The moto-taxi dudes at the gas station told me that buses from there go to Laos. Good to know. Thanks.
The next day I checked w/ some visa-border-run tour operators and several suggested that I stand at a random bus stop on the Sukhumvit Highway and try to flag down a bus that had "Chanthaburi" written on it somewhere. OK. I went to the highway out of curiosity and looked around and forget that shit. I even followed a Dutch(?) guy to yesterday's gas station bus stop where he translated what the bus lady said. That is, to go back to the south-bound side of the highway (again) and to walk south to the next gas station and then 50 meters further to a 2nd (3rd? 4th? I've lost count by now.) bus station. I went there, but no buses to Chanthaburi. The lady at that 2nd bus station suggested I check the (5th? 98th?) bus station directly across the highway, which meant walking all the way back to the pedestrian crossover by the first gas station. Sheesh!
When I got near the crossover I started asking around and a different set of moto-taxi dudes told me to go one street north of the Num Chai and follow it about 1/2 kilometer east (head towards the Tesco Lotus) to the Chanthaburi minibus stop/office with the "Express" sign (map). And whattaya know? There it was! I was very happy.
Minibuses leave for Chanthaburi from that "Express" stop/office every hour or so from 06:00 thru 18:00 (200 baht, ~US$5.75). The trip takes about 3 hours, depending on how many different passenger stops there are. It's called "Express", but many stops were made.
And now for the technical details (5 vehicles) of the journey (to Battambang) itself: I took a private taxi* (250 baht, ~US$7.15) to the "Express" stop/office at 9:30am and got a spot on the 11am bus which actually left at 10:35am, when the minibus was full. The final stop was at a (real) Chanthaburi bus station where I hired a small-sized, private-ride songthaew (3 mins, 60 baht, ~US$1.75) to take me to a much larger songthaew heading to Ban Pakard/Prum (2? hours, 100 baht, ~US$2.85). (There was no minibus available until the evening.) I think we left around 2pm. 3 different Thai women helped with the translations. An Italian couple also got on the larger songthaew. I was relieved and thought, "Ah! Someone else has made the same mistake." (One of them later told me he was relieved to see me, too.) At the border we (the two Italians and I) each paid US$35 (or 1300 baht also accepted) to the Cambodian government. We shared a taxi to Battambang (1.5? hours, US$11 ea), arriving around 7:30pm. We got rooms at the Banan Hotel, US$15 for me.
At this time, Cambodia used US dollars in conjunction with the Cambodian Riel. US$1 = 4000 CR = 35 Thai baht.
*I believe I way overpaid for that taxi. I should have had him run the meter.
Whew, that's a long story.