Bukit Mertajam is in Penang.
There are two main express bus stations in Penang, Butterworth Bus Terminal near the ferry terminal and KTM train station and Sungai Nibong Bus Terminal on Penang Island (around 10 minutes drive from Butterworth). Bukit Mertajam is just a short distance away from Butterworth Bus / KTM (Train) / Ferry terminal. To get to Butterworth Bus terminal, take an express bus. Many major bus companies like Transnasional, Konsortium, Sri Maju, Suasana Edaran and Aeroline go to Penang / Butterworth / Georgetown. You can find the express bus schedules at Roadhop. The bus driver will drop you off direct at Bukit Mertajam. If that is not possible, take the ferry from Butterworth Bus terminal to Penang Sentral local bus terminal on Penang Island. When you arrive, take bus 701 and 702 from Rapidpenang for around 2.7RM to go to Bukit Mertajam. For bus, you might have to wait 30mins-50mins for the bus to come. But it's much cheaper.
Alternatively, you can take the KTM train. There are a number of lines to choose from, for example, Express Rakyat 1 and Express Langkawi EL8. Trains are really convenient if you are coming from locations without express bus terminals! Bukit Mertajam was a major railway hub for both passengers and cargo. If you drive to Bukit Mertajam, you will encounter a surprising number of railway crossings everywhere. There is one coming from the short cut from Permatang Tinggi and two coming from Permatang Tengah. Moreover, the railway station once won the most beautiful station in Malaysia award.
If you can also take a taxi from Penang Sentral to Bukit Mertajam, but you risk having a high fare because of the traffic. It will cost around RM 30-50 for a day trip or RM 120-150 at night. Ironically, the taxi drivers at Sungai Nibong Bus Terminal actually charge much less and have a fixed price! In Bukit Mertajam, there are local buses connecting from towns like Kulim and Parit Buntar. It is also a short distance away from the beach resorts at Batu Ferringhi.
Most of the car rental places in Penang are located at the airport, so if you will like to drive to Bukit Mertajam, it is better to fly in using one of the budget flights and rent a car.
The only public transport available in the town is bus, however, you can travel around with taxi too. But bare in mind, you rarely able to get a taxi on the street. Normally, you only can get the taxi from the main taxi terminal. And, there might be only have one bus in every 1 or 2 hour once.
The Summit Hotel, Palm inn, My Hotel Kampung Baru